Only log the keys in the "extras" dictionary when instantiating objects from_params (#2608)

Author: matt-gardner

allennlp/common/from_params.py

@@ -254,7 +254,7 @@ def from_params(cls: Type[T], params: Params, **extras) -> T:
         from allennlp.common.registrable import Registrable  # import here to avoid circular imports
 
         logger.info(f"instantiating class {cls} from params {getattr(params, 'params', params)} "
-                    f"and extras {extras}")
+                    f"and extras {set(extras.keys())}")
 
         if params is None:
             return None