Add deprecation warnings to load_wav functions (#905)

Author: mthrok

torchaudio/backend/soundfile_backend.py

@@ -73,6 +73,7 @@ def load(filepath: str,
 
 
 @_mod_utils.requires_module('soundfile')
+@_mod_utils.deprecated('Please use "torchaudio.load".', '0.9.0')
 @common._impl_load_wav
 def load_wav(filepath, **kwargs):
     kwargs['normalization'] = 1 << 16

torchaudio/backend/sox_backend.py

@@ -63,6 +63,7 @@ def load(filepath: str,
 
 
 @_mod_utils.requires_module('torchaudio._torchaudio')
+@_mod_utils.deprecated('Please use "torchaudio.load".', '0.9.0')
 @common._impl_load_wav
 def load_wav(filepath, **kwargs):
     kwargs['normalization'] = 1 << 16

torchaudio/backend/sox_io_backend.py

@@ -175,6 +175,7 @@ def save(
 
 
 @_mod_utils.requires_module('torchaudio._torchaudio')
+@_mod_utils.deprecated('Please use "torchaudio.load".', '0.9.0')
 def load_wav(
         filepath: str,
         frame_offset: int = 0,