From b0d96ae415bdae1394a0154d271dfcd2d3063739 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Fri, 1 Jul 2022 07:53:17 -0400
Subject: [PATCH 01/24] remove corresponding line from pyproject.toml

---
 pyproject.toml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 4b9f45068e089..dcd319835deb4 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -55,7 +55,6 @@ module = [
     "pytorch_lightning.demos.mnist_datamodule",
     "pytorch_lightning.distributed.dist",
     "pytorch_lightning.loggers.base",
-    "pytorch_lightning.loggers.logger",
     "pytorch_lightning.loggers.comet",
     "pytorch_lightning.loggers.csv_logs",
     "pytorch_lightning.loggers.mlflow",

From 5bf3cce044be5db18816db1151867e26aaca2fe8 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:23:03 -0400
Subject: [PATCH 02/24] add notebooks

---
 _notebooks | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/_notebooks b/_notebooks
index 8a36a41548f34..f48fad5489272 160000
--- a/_notebooks
+++ b/_notebooks
@@ -1 +1 @@
-Subproject commit 8a36a41548f34c44ac455d515a72994487e85813
+Subproject commit f48fad5489272af915f25e98320badfca600c588

From a6f2cd54e947b345065ad5b74261c29e0c6813ff Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:28:25 -0400
Subject: [PATCH 03/24] add notebooks

---
 _notebooks | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/_notebooks b/_notebooks
index f48fad5489272..85bdeeeb4ef7e 160000
--- a/_notebooks
+++ b/_notebooks
@@ -1 +1 @@
-Subproject commit f48fad5489272af915f25e98320badfca600c588
+Subproject commit 85bdeeeb4ef7ea8b5c7cd1a4309321becc57cddb

From b701321dfd464e1a3cc81a688c85ff74e32028fb Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:34:41 -0400
Subject: [PATCH 04/24] update rank_zero_experiment

---
 src/pytorch_lightning/loggers/logger.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index d532aae413650..60eaef7de1913 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -33,9 +33,9 @@ def rank_zero_experiment(fn: Callable) -> Callable:
     """Returns the real experiment on rank 0 and otherwise the DummyExperiment."""
 
     @wraps(fn)
-    def experiment(self):
+    def experiment(self: type) -> Union[Any, DummyExperiment]:
         @rank_zero_only
-        def get_experiment():
+        def get_experiment() -> Callable:
             return fn(self)
 
         return get_experiment() or DummyExperiment()

From 576c6c79acad24b2a4247434e28f56c7bc370983 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:36:24 -0400
Subject: [PATCH 05/24] update update_agg_funcs

---
 src/pytorch_lightning/loggers/logger.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 60eaef7de1913..216ac6e23ba8e 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -98,7 +98,7 @@ def update_agg_funcs(
         self,
         agg_key_funcs: Optional[Mapping[str, Callable[[Sequence[float]], float]]] = None,
         agg_default_func: Callable[[Sequence[float]], float] = np.mean,
-    ):
+    ) -> None:
         """Update aggregation methods.
 
         .. deprecated:: v1.6

From 8d682bde8a874977f71897c9e149a4e8387e3bc8 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:40:43 -0400
Subject: [PATCH 06/24] update agg_and_log_metrics and log_metrics

---
 src/pytorch_lightning/loggers/logger.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 216ac6e23ba8e..a6ecb57fbb524 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -119,7 +119,7 @@ def update_agg_funcs(
             self._agg_default_func = agg_default_func
         rank_zero_deprecation("`Logger.update_agg_funcs` was deprecated in v1.6 and will be removed in v1.8.")
 
-    def agg_and_log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None):
+    def agg_and_log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) -> None:
         """Aggregates and records metrics. This method doesn't log the passed metrics instantaneously, but instead
         it aggregates them and logs only if metrics are ready to be logged.
 
@@ -134,7 +134,7 @@ def agg_and_log_metrics(self, metrics: Dict[str, float], step: Optional[int] = N
         self.log_metrics(metrics=metrics, step=step)
 
     @abstractmethod
-    def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None):
+    def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) -> None:
         """
         Records metrics.
         This method logs metrics as as soon as it received them. If you want to aggregate

From 14ce08e5ae75087efeff4aa9410f539a37fcfe5a Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:41:50 -0400
Subject: [PATCH 07/24] update log_hyperparams annotations and return type

---
 src/pytorch_lightning/loggers/logger.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index a6ecb57fbb524..b2bc2e31ab7cf 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -148,7 +148,7 @@ def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) ->
         pass
 
     @abstractmethod
-    def log_hyperparams(self, params: argparse.Namespace, *args, **kwargs):
+    def log_hyperparams(self, params: argparse.Namespace, *args: Any, **kwargs: Any) -> None:
         """Record hyperparameters.
 
         Args:

From e077e117e3765ee89afbf47b051f7edb2885d68e Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 22:56:35 -0400
Subject: [PATCH 08/24] update log_graph annotation

---
 src/pytorch_lightning/loggers/logger.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index b2bc2e31ab7cf..4d3b05ff71c1b 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -23,6 +23,7 @@
 from weakref import ReferenceType
 
 import numpy as np
+from torch import Tensor
 
 import pytorch_lightning as pl
 from pytorch_lightning.callbacks import Checkpoint
@@ -157,7 +158,7 @@ def log_hyperparams(self, params: argparse.Namespace, *args: Any, **kwargs: Any)
             kwargs: Optional keyword arguments, depends on the specific logger being used
         """
 
-    def log_graph(self, model: "pl.LightningModule", input_array=None) -> None:
+    def log_graph(self, model: "pl.LightningModule", input_array: Tensor = None) -> None:
         """Record model graph.
 
         Args:

From 725df82b441e311e4ff46edbaf59c8d19c1c1aaa Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 23:02:42 -0400
Subject: [PATCH 09/24] update multiple None return types

---
 src/pytorch_lightning/loggers/logger.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 4d3b05ff71c1b..62665a1a1ab8d 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -185,7 +185,7 @@ def save_dir(self) -> Optional[str]:
         return None
 
     @property
-    def group_separator(self):
+    def group_separator(self) -> str:
         """Return the default separator used by the logger to group the data into subfolders."""
         return "/"
 
@@ -230,7 +230,7 @@ def update_agg_funcs(
         self,
         agg_key_funcs: Optional[Mapping[str, Callable[[Sequence[float]], float]]] = None,
         agg_default_func: Callable[[Sequence[float]], float] = np.mean,
-    ):
+    ) -> None:
         for logger in self._logger_iterable:
             logger.update_agg_funcs(agg_key_funcs, agg_default_func)
 
@@ -239,7 +239,7 @@ def experiment(self) -> List[Any]:
         """Returns a list of experiment objects for all the loggers in the logger collection."""
         return [logger.experiment for logger in self._logger_iterable]
 
-    def agg_and_log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None):
+    def agg_and_log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) -> None:
         for logger in self._logger_iterable:
             logger.agg_and_log_metrics(metrics=metrics, step=step)
 
@@ -251,7 +251,7 @@ def log_hyperparams(self, params: Union[Dict[str, Any], Namespace]) -> None:
         for logger in self._logger_iterable:
             logger.log_hyperparams(params)
 
-    def log_graph(self, model: "pl.LightningModule", input_array=None) -> None:
+    def log_graph(self, model: "pl.LightningModule", input_array: Tensor = None) -> None:
         for logger in self._logger_iterable:
             logger.log_graph(model, input_array)
 
@@ -259,7 +259,7 @@ def log_text(self, *args, **kwargs) -> None:
         for logger in self._logger_iterable:
             logger.log_text(*args, **kwargs)
 
-    def log_image(self, *args, **kwargs) -> None:
+    def log_image(self, *args: Any, **kwargs: Any) -> None:
         for logger in self._logger_iterable:
             logger.log_image(*args, **kwargs)
 

From 2b9dcbea2f813b36aa5134c62b42886ca8fa97ae Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Mon, 4 Jul 2022 23:08:11 -0400
Subject: [PATCH 10/24] update DummyExperiment and log_text

---
 src/pytorch_lightning/loggers/logger.py | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 62665a1a1ab8d..f9b36534f13eb 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -255,7 +255,7 @@ def log_graph(self, model: "pl.LightningModule", input_array: Tensor = None) ->
         for logger in self._logger_iterable:
             logger.log_graph(model, input_array)
 
-    def log_text(self, *args, **kwargs) -> None:
+    def log_text(self, *args: Any, **kwargs: Any) -> None:
         for logger in self._logger_iterable:
             logger.log_text(*args, **kwargs)
 
@@ -294,17 +294,17 @@ def version(self) -> str:
 class DummyExperiment:
     """Dummy experiment."""
 
-    def nop(self, *args, **kw):
+    def nop(self, *args: Any, **kw: Any) -> None:
         pass
 
-    def __getattr__(self, _):
+    def __getattr__(self, _: Any) -> Callable:
         return self.nop
 
-    def __getitem__(self, idx) -> "DummyExperiment":
+    def __getitem__(self, idx: int) -> "DummyExperiment":
         # enables self.logger.experiment[0].add_image(...)
         return self
 
-    def __setitem__(self, *args, **kwargs) -> None:
+    def __setitem__(self, *args: Any, **kwargs: Any) -> None:
         pass
 
 

From 6ec8365bd8d9e4ad2dc6727671b5d092a6c7daef Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 07:24:15 -0400
Subject: [PATCH 11/24] update DummyLogger

---
 src/pytorch_lightning/loggers/logger.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index f9b36534f13eb..6f96b8f981797 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -323,10 +323,10 @@ def experiment(self) -> DummyExperiment:
         """Return the experiment object associated with this logger."""
         return self._experiment
 
-    def log_metrics(self, *args, **kwargs) -> None:
+    def log_metrics(self, *args: Any, **kwargs: Any) -> None:
         pass
 
-    def log_hyperparams(self, *args, **kwargs) -> None:
+    def log_hyperparams(self, *args: Any, **kwargs: Any) -> None:
         pass
 
     @property
@@ -339,7 +339,7 @@ def version(self) -> str:
         """Return the experiment version."""
         return ""
 
-    def __getitem__(self, idx) -> "DummyLogger":
+    def __getitem__(self, idx: int) -> "DummyLogger":
         # enables self.logger[0].experiment.add_image(...)
         return self
 
@@ -350,7 +350,7 @@ def __iter__(self):
     def __getattr__(self, name: str) -> Callable:
         """Allows the DummyLogger to be called with arbitrary methods, to avoid AttributeErrors."""
 
-        def method(*args, **kwargs):
+        def method(*args: Any, **kwargs: Any) -> None:
             return None
 
         return method

From 6df935d6867649b505522d7a850f65bf8040f809 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 08:40:21 -0400
Subject: [PATCH 12/24] fix return types for rank_zero_experiment

---
 src/pytorch_lightning/loggers/logger.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 6f96b8f981797..bfdda91c1f7e6 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -16,6 +16,7 @@
 import argparse
 import functools
 import operator
+import typing as t
 from abc import ABC, abstractmethod
 from argparse import Namespace
 from functools import wraps
@@ -29,12 +30,15 @@
 from pytorch_lightning.callbacks import Checkpoint
 from pytorch_lightning.utilities.rank_zero import rank_zero_deprecation, rank_zero_only
 
+if t.TYPE_CHECKING:
+    from pytorch_lightning.loggers.csv_logs import ExperimentWriter
+
 
 def rank_zero_experiment(fn: Callable) -> Callable:
     """Returns the real experiment on rank 0 and otherwise the DummyExperiment."""
 
     @wraps(fn)
-    def experiment(self: type) -> Union[Any, DummyExperiment]:
+    def experiment(self: Callable) -> Union[ExperimentWriter, DummyExperiment]:
         @rank_zero_only
         def get_experiment() -> Callable:
             return fn(self)

From b67e68f2df05a6ffcceb097b83759ae8ce059ded Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 09:07:31 -0400
Subject: [PATCH 13/24] update DummyLogger

---
 src/pytorch_lightning/loggers/logger.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index bfdda91c1f7e6..8d6cfe45ec097 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -20,7 +20,7 @@
 from abc import ABC, abstractmethod
 from argparse import Namespace
 from functools import wraps
-from typing import Any, Callable, Dict, Iterable, List, Mapping, Optional, Sequence, Union
+from typing import Any, Callable, Collection, Dict, Iterable, List, Mapping, Optional, Sequence, Union
 from weakref import ReferenceType
 
 import numpy as np
@@ -318,7 +318,7 @@ class DummyLogger(Logger):
     It is useful if we want to disable user's logger for a feature, but still ensure that user code can run
     """
 
-    def __init__(self):
+    def __init__(self) -> None:
         super().__init__()
         self._experiment = DummyExperiment()
 
@@ -347,7 +347,7 @@ def __getitem__(self, idx: int) -> "DummyLogger":
         # enables self.logger[0].experiment.add_image(...)
         return self
 
-    def __iter__(self):
+    def __iter__(self) -> Iterable[Collection]:
         # if DummyLogger is substituting a logger collection, pretend it is empty
         yield from ()
 

From 01112c1f0e53847af6576d101616943db3f47da7 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 09:15:53 -0400
Subject: [PATCH 14/24] update Logger.log_hyperparams

---
 src/pytorch_lightning/loggers/logger.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 8d6cfe45ec097..413fe10623cc0 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 """Abstract base class used to build new loggers."""
 
-import argparse
+
 import functools
 import operator
 import typing as t
@@ -153,11 +153,11 @@ def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) ->
         pass
 
     @abstractmethod
-    def log_hyperparams(self, params: argparse.Namespace, *args: Any, **kwargs: Any) -> None:
+    def log_hyperparams(self, params: Union[Dict[str, Any], Namespace], *args: Any, **kwargs: Any) -> None:
         """Record hyperparameters.
 
         Args:
-            params: :class:`~argparse.Namespace` containing the hyperparameters
+            params: :class:`~argparse.Namespace` or `Dict` containing the hyperparameters
             args: Optional positional arguments, depends on the specific logger being used
             kwargs: Optional keyword arguments, depends on the specific logger being used
         """

From b75fb460346c91e98deb974ba8b452c5abac602f Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 10:16:11 -0400
Subject: [PATCH 15/24] updated DummyLogger.__iter__ return type

---
 src/pytorch_lightning/loggers/logger.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 413fe10623cc0..ece1888a0ccee 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -20,7 +20,7 @@
 from abc import ABC, abstractmethod
 from argparse import Namespace
 from functools import wraps
-from typing import Any, Callable, Collection, Dict, Iterable, List, Mapping, Optional, Sequence, Union
+from typing import Any, Callable, Dict, Generator, Iterable, List, Mapping, Optional, Sequence, Union
 from weakref import ReferenceType
 
 import numpy as np
@@ -347,7 +347,7 @@ def __getitem__(self, idx: int) -> "DummyLogger":
         # enables self.logger[0].experiment.add_image(...)
         return self
 
-    def __iter__(self) -> Iterable[Collection]:
+    def __iter__(self) -> Generator[None, None, None]:
         # if DummyLogger is substituting a logger collection, pretend it is empty
         yield from ()
 

From 3e21af15c0ee4aa045d372608e48df87a2d39412 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 10:34:33 -0400
Subject: [PATCH 16/24] update log_hyperparams

---
 src/pytorch_lightning/loggers/logger.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index ece1888a0ccee..b45fe3a96db8c 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -251,9 +251,9 @@ def log_metrics(self, metrics: Dict[str, float], step: Optional[int] = None) ->
         for logger in self._logger_iterable:
             logger.log_metrics(metrics=metrics, step=step)
 
-    def log_hyperparams(self, params: Union[Dict[str, Any], Namespace]) -> None:
+    def log_hyperparams(self, params: Union[Dict[str, Any], Namespace], *args: Any, **kwargs: Any) -> None:
         for logger in self._logger_iterable:
-            logger.log_hyperparams(params)
+            logger.log_hyperparams(params, *args, **kwargs)
 
     def log_graph(self, model: "pl.LightningModule", input_array: Tensor = None) -> None:
         for logger in self._logger_iterable:

From fd235cd7e31fa5adb7b4bd96601eee178e8538a6 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 17:46:20 -0400
Subject: [PATCH 17/24] update merge_dicts

---
 src/pytorch_lightning/loggers/logger.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index b45fe3a96db8c..fc7cd035181b2 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -19,6 +19,7 @@
 import typing as t
 from abc import ABC, abstractmethod
 from argparse import Namespace
+from collections import defaultdict
 from functools import wraps
 from typing import Any, Callable, Dict, Generator, Iterable, List, Mapping, Optional, Sequence, Union
 from weakref import ReferenceType
@@ -362,7 +363,7 @@ def method(*args: Any, **kwargs: Any) -> None:
 
 def merge_dicts(
     dicts: Sequence[Mapping],
-    agg_key_funcs: Optional[Mapping[str, Callable[[Sequence[float]], float]]] = None,
+    agg_key_funcs: Optional[Mapping] = None,
     default_func: Callable[[Sequence[float]], float] = np.mean,
 ) -> Dict:
     """Merge a sequence with dictionaries into one dictionary by aggregating the same keys with some given
@@ -400,7 +401,7 @@ def merge_dicts(
     """
     agg_key_funcs = agg_key_funcs or {}
     keys = list(functools.reduce(operator.or_, [set(d.keys()) for d in dicts]))
-    d_out = {}
+    d_out: Dict = defaultdict(dict)
     for k in keys:
         fn = agg_key_funcs.get(k)
         values_to_agg = [v for v in [d_in.get(k) for d_in in dicts] if v is not None]

From 0976466de2e0fc75bb609bba5b932c9e785c56d6 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Tue, 5 Jul 2022 17:49:33 -0400
Subject: [PATCH 18/24] update return

---
 src/pytorch_lightning/loggers/logger.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index fc7cd035181b2..a0f5eb74e1b69 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -411,4 +411,4 @@ def merge_dicts(
         else:
             d_out[k] = (fn or default_func)(values_to_agg)
 
-    return d_out
+    return dict(d_out)

From 2e9a0a668af0df6c57574afb9ee66c5e32c6f11c Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Wed, 6 Jul 2022 07:55:55 -0400
Subject: [PATCH 19/24] Update src/pytorch_lightning/loggers/logger.py
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Co-authored-by: Adrian Wälchli <aedu.waelchli@gmail.com>
---
 src/pytorch_lightning/loggers/logger.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index a0f5eb74e1b69..72bf4034f21ac 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -31,7 +31,7 @@
 from pytorch_lightning.callbacks import Checkpoint
 from pytorch_lightning.utilities.rank_zero import rank_zero_deprecation, rank_zero_only
 
-if t.TYPE_CHECKING:
+if TYPE_CHECKING:
     from pytorch_lightning.loggers.csv_logs import ExperimentWriter
 
 

From b4c3ed514f32e4f346b83efa43b23e500b9ce23a Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Wed, 6 Jul 2022 08:41:29 -0400
Subject: [PATCH 20/24] change rank_zero_experiment; update import statements

---
 src/pytorch_lightning/loggers/logger.py | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 72bf4034f21ac..acb31cbf49f20 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -16,12 +16,11 @@
 
 import functools
 import operator
-import typing as t
 from abc import ABC, abstractmethod
 from argparse import Namespace
 from collections import defaultdict
 from functools import wraps
-from typing import Any, Callable, Dict, Generator, Iterable, List, Mapping, Optional, Sequence, Union
+from typing import Any, Callable, Dict, Generator, Iterable, List, Mapping, Optional, Sequence, TYPE_CHECKING, Union
 from weakref import ReferenceType
 
 import numpy as np
@@ -39,7 +38,7 @@ def rank_zero_experiment(fn: Callable) -> Callable:
     """Returns the real experiment on rank 0 and otherwise the DummyExperiment."""
 
     @wraps(fn)
-    def experiment(self: Callable) -> Union[ExperimentWriter, DummyExperiment]:
+    def experiment(self) -> Union[ExperimentWriter, DummyExperiment]:  # type: ignore[no-untyped-def]
         @rank_zero_only
         def get_experiment() -> Callable:
             return fn(self)

From 0382fb008841a7427c79b520f91393bbf1bc3e76 Mon Sep 17 00:00:00 2001
From: Akihiro Nitta <nitta@akihironitta.com>
Date: Fri, 8 Jul 2022 09:09:59 +0900
Subject: [PATCH 21/24] Revert notebooks

---
 _notebooks | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/_notebooks b/_notebooks
index 85bdeeeb4ef7e..8a36a41548f34 160000
--- a/_notebooks
+++ b/_notebooks
@@ -1 +1 @@
-Subproject commit 85bdeeeb4ef7ea8b5c7cd1a4309321becc57cddb
+Subproject commit 8a36a41548f34c44ac455d515a72994487e85813

From 2f78109c2e38230179b301bdb817a4ce8c7d7a4e Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Fri, 8 Jul 2022 20:27:04 -0400
Subject: [PATCH 22/24] remove conditional import statement

---
 src/pytorch_lightning/loggers/logger.py | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index acb31cbf49f20..c0b98a4e58b01 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -20,7 +20,7 @@
 from argparse import Namespace
 from collections import defaultdict
 from functools import wraps
-from typing import Any, Callable, Dict, Generator, Iterable, List, Mapping, Optional, Sequence, TYPE_CHECKING, Union
+from typing import Any, Callable, Dict, Generator, Iterable, List, Mapping, Optional, Sequence, Union
 from weakref import ReferenceType
 
 import numpy as np
@@ -28,11 +28,9 @@
 
 import pytorch_lightning as pl
 from pytorch_lightning.callbacks import Checkpoint
+from pytorch_lightning.loggers.csv_logs import ExperimentWriter
 from pytorch_lightning.utilities.rank_zero import rank_zero_deprecation, rank_zero_only
 
-if TYPE_CHECKING:
-    from pytorch_lightning.loggers.csv_logs import ExperimentWriter
-
 
 def rank_zero_experiment(fn: Callable) -> Callable:
     """Returns the real experiment on rank 0 and otherwise the DummyExperiment."""

From 5d2d31436b69c25b2c4a6f925e32c94d768182b2 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Fri, 8 Jul 2022 20:53:43 -0400
Subject: [PATCH 23/24] update log_graph

---
 src/pytorch_lightning/loggers/logger.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index c0b98a4e58b01..829c65d342297 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -160,7 +160,7 @@ def log_hyperparams(self, params: Union[Dict[str, Any], Namespace], *args: Any,
             kwargs: Optional keyword arguments, depends on the specific logger being used
         """
 
-    def log_graph(self, model: "pl.LightningModule", input_array: Tensor = None) -> None:
+    def log_graph(self, model: "pl.LightningModule", input_array: Optional[Tensor] = None) -> None:
         """Record model graph.
 
         Args:
@@ -253,7 +253,7 @@ def log_hyperparams(self, params: Union[Dict[str, Any], Namespace], *args: Any,
         for logger in self._logger_iterable:
             logger.log_hyperparams(params, *args, **kwargs)
 
-    def log_graph(self, model: "pl.LightningModule", input_array: Tensor = None) -> None:
+    def log_graph(self, model: "pl.LightningModule", input_array: Optional[Tensor] = None) -> None:
         for logger in self._logger_iterable:
             logger.log_graph(model, input_array)
 

From a75cd2e005369229f72ad5412a9779ec01db6462 Mon Sep 17 00:00:00 2001
From: Justin Goheen <26209687+JustinGoheen@users.noreply.github.com>
Date: Sun, 10 Jul 2022 11:29:10 -0400
Subject: [PATCH 24/24] fix rank_zero_experiment

---
 src/pytorch_lightning/loggers/logger.py | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/pytorch_lightning/loggers/logger.py b/src/pytorch_lightning/loggers/logger.py
index 829c65d342297..4113b61627d8f 100644
--- a/src/pytorch_lightning/loggers/logger.py
+++ b/src/pytorch_lightning/loggers/logger.py
@@ -28,7 +28,6 @@
 
 import pytorch_lightning as pl
 from pytorch_lightning.callbacks import Checkpoint
-from pytorch_lightning.loggers.csv_logs import ExperimentWriter
 from pytorch_lightning.utilities.rank_zero import rank_zero_deprecation, rank_zero_only
 
 
@@ -36,7 +35,18 @@ def rank_zero_experiment(fn: Callable) -> Callable:
     """Returns the real experiment on rank 0 and otherwise the DummyExperiment."""
 
     @wraps(fn)
-    def experiment(self) -> Union[ExperimentWriter, DummyExperiment]:  # type: ignore[no-untyped-def]
+    def experiment(self) -> Union[Any, DummyExperiment]:  # type: ignore[no-untyped-def]
+        """
+        Note:
+            `self` is a custom logger instance. The loggers typical wrap an `experiment` method
+            with a @rank_zero_experiment decorator. An exception being `loggers.neptune` wraps
+            `experiment` and `run` with rank_zero_experiment.
+
+            Union[Any, DummyExperiment] is used because the wrapped hooks have several returns
+            types that are specific to the custom logger. The return type can be considered as
+            Union[return type of logger.experiment, DummyExperiment]
+        """
+
         @rank_zero_only
         def get_experiment() -> Callable:
             return fn(self)