chore(session): Add TYPE_CHECKING: Try to avoid circular imports

Author: tony

libtmux/session.py

@@ -18,9 +18,13 @@
     has_version,
     session_check_name,
 )
-from .pane import Pane
 from .window import Window
 
+if t.TYPE_CHECKING:
+    from .pane import Pane
+    from .server import Server
+
+
 logger = logging.getLogger(__name__)
 
 
@@ -52,7 +56,7 @@ class Session(TmuxMappingObject, TmuxRelationalObject, EnvironmentMixin):
     #: namespace used :class:`~libtmux.common.TmuxMappingObject`
     formatter_prefix = "session_"
 
-    def __init__(self, server=None, **kwargs):
+    def __init__(self, server: t.Optional["Server"] = None, **kwargs):
         EnvironmentMixin.__init__(self)
         self.server = server
 
@@ -367,7 +371,7 @@ def select_window(self, target_window: str) -> Window:
         return self.attached_window
 
     @property
-    def attached_pane(self) -> t.Optional[Pane]:
+    def attached_pane(self) -> t.Optional["Pane"]:
         """Return active :class:`Pane` object."""
 
         return self.attached_window.attached_pane