Stop assigning output_fd in Default formatter

flake8/formatting/default.py

@@ -13,7 +13,6 @@ class Default(base.BaseFormatter):
 
     def after_init(self):
         """Check for a custom format string."""
-        self.output_fd = None
         if self.options.format.lower() != 'default':
             self.error_format = self.options.format
 

flake8/main/cli.py

@@ -174,3 +174,7 @@ def main(argv=None):
     # Parse out our options from our found config files and user-provided CLI
     # options
     options, args = aggregator.aggregate_options(option_manager)
+
+    # formatter = formatting_plugins.get(
+    #     options.format, formatting_plugins['default']
+    # ).execute(options)