old_contents: """Show diff for a file in the Dodo Commands system directory."""
  
  from . import DodoCommand
  from six.moves import configparser
  import os
  
  
  class Command(DodoCommand):  # noqa
      def add_arguments_imp(self, parser):  # noqa
          """
          Entry point for subclassed commands to add custom arguments.
          """
          parser.add_argument(
              'file',
              help='Show diff for this file'
          )
  
      def handle_imp(self, file, **kwargs):  # noqa
          project_dir = self.get_config("/ROOT/project_dir", "")
          system_dir = self.get_config("/ROOT/system_dir", "")
          project_name = self.get_config("/ROOT/project_name", "")
  
          config = configparser.ConfigParser()
          config.read(os.path.join(system_dir, "dodo_commands.config"))
  
          diff_tool = config.get("DodoCommands", "diff_tool")
          res_dir = os.path.join(project_dir, "dodo_commands", "res")
  
          original_file = os.path.join(
              system_dir, "defaults", "projects", project_name, file)
          copied_file = os.path.join(res_dir, file)
  
          self.runcmd(
              [diff_tool, original_file, copied_file],
              cwd=res_dir
          )
  
new_contents: """Show diff for a file in the Dodo Commands system directory."""
  
  from . import DodoCommand
  from six.moves import configparser
  import os
  
  
  class Command(DodoCommand):  # noqa
      def add_arguments_imp(self, parser):  # noqa
          """
          Entry point for subclassed commands to add custom arguments.
          """
          parser.add_argument(
              'file',
              help='Show diff for this file'
          )
  
      def handle_imp(self, file, **kwargs):  # noqa
          project_dir = self.get_config("/ROOT/project_dir", "")
          system_dir = self.get_config("/ROOT/system_dir", "")
  
          config = configparser.ConfigParser()
          config.read(os.path.join(system_dir, "dodo_commands.config"))
  
          diff_tool = config.get("DodoCommands", "diff_tool")
          res_dir = os.path.join(project_dir, "dodo_commands", "res")
  
          original_file = os.path.realpath(
              os.path.join(project_dir, "dodo_commands", "defaults", "project")
          )
          copied_file = os.path.join(res_dir, file)
  
          self.runcmd(
              [diff_tool, original_file, copied_file],
              cwd=res_dir
          )
  
subject: Use symlink dodo_commands/defaults/project in diff command