diff --git a/TTS/bin/collect_env_info.py b/TTS/bin/collect_env_info.py
index dcd52fea..662fcd02 100644
--- a/TTS/bin/collect_env_info.py
+++ b/TTS/bin/collect_env_info.py
@@ -8,8 +8,10 @@ import torch
 
 sys.path += [os.path.abspath(".."), os.path.abspath(".")]
 import json
+
 import TTS
 
+
 def system_info():
     return {
         "OS": platform.system(),
diff --git a/TTS/utils/callbacks.py b/TTS/utils/callbacks.py
index 3746eb15..511d215c 100644
--- a/TTS/utils/callbacks.py
+++ b/TTS/utils/callbacks.py
@@ -1,8 +1,6 @@
 class TrainerCallback:
-    def __init__(self):
-        super().__init__()
-
-    def on_init_start(self, trainer) -> None:
+    @staticmethod
+    def on_init_start(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_init_start"):
                 trainer.model.module.on_init_start(trainer)
@@ -16,7 +14,8 @@ class TrainerCallback:
         if hasattr(trainer.optimizer, "on_init_start"):
             trainer.optimizer.on_init_start(trainer)
 
-    def on_init_end(self, trainer) -> None:
+    @staticmethod
+    def on_init_end(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_init_end"):
                 trainer.model.module.on_init_end(trainer)
@@ -30,7 +29,8 @@ class TrainerCallback:
         if hasattr(trainer.optimizer, "on_init_end"):
             trainer.optimizer.on_init_end(trainer)
 
-    def on_epoch_start(self, trainer) -> None:
+    @staticmethod
+    def on_epoch_start(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_epoch_start"):
                 trainer.model.module.on_epoch_start(trainer)
@@ -44,7 +44,8 @@ class TrainerCallback:
         if hasattr(trainer.optimizer, "on_epoch_start"):
             trainer.optimizer.on_epoch_start(trainer)
 
-    def on_epoch_end(self, trainer) -> None:
+    @staticmethod
+    def on_epoch_end(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_epoch_end"):
                 trainer.model.module.on_epoch_end(trainer)
@@ -58,7 +59,8 @@ class TrainerCallback:
         if hasattr(trainer.optimizer, "on_epoch_end"):
             trainer.optimizer.on_epoch_end(trainer)
 
-    def on_train_step_start(self, trainer) -> None:
+    @staticmethod
+    def on_train_step_start(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_train_step_start"):
                 trainer.model.module.on_train_step_start(trainer)
@@ -72,7 +74,8 @@ class TrainerCallback:
         if hasattr(trainer.optimizer, "on_train_step_start"):
             trainer.optimizer.on_train_step_start(trainer)
 
-    def on_train_step_end(self, trainer) -> None:
+    @staticmethod
+    def on_train_step_end(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_train_step_end"):
                 trainer.model.module.on_train_step_end(trainer)
@@ -86,7 +89,8 @@ class TrainerCallback:
         if hasattr(trainer.optimizer, "on_train_step_end"):
             trainer.optimizer.on_train_step_end(trainer)
 
-    def on_keyboard_interrupt(self, trainer) -> None:
+    @staticmethod
+    def on_keyboard_interrupt(trainer) -> None:
         if hasattr(trainer.model, "module"):
             if hasattr(trainer.model.module, "on_keyboard_interrupt"):
                 trainer.model.module.on_keyboard_interrupt(trainer)
diff --git a/TTS/vocoder/models/gan.py b/TTS/vocoder/models/gan.py
index 1b49831e..e36c2cd1 100644
--- a/TTS/vocoder/models/gan.py
+++ b/TTS/vocoder/models/gan.py
@@ -310,7 +310,7 @@ class GAN(BaseVocoder):
         data_items: List,
         verbose: bool,
         num_gpus: int,
-        rank:int=0
+        rank: int = 0,  # pylint: disable=unused-argument
     ):
         """Initiate and return the GAN dataloader.