Remove/Edit docstrings to be compatible with PEP257

Author: ahsan-z-khan

src/sagemaker/tensorflow/model.py

@@ -348,7 +348,7 @@ def prepare_container_def(self, instance_type=None, accelerator_type=None):
         return sagemaker.container_def(image_uri, model_data, env)
 
     def _get_container_env(self):
-        """Placeholder docstring"""
+
         if not self._container_log_level:
             return self.env