code: def delete_file(self, path, prefixed_path, source_storage):
          
          if self.storage.exists(prefixed_path):
              try:
                  # When was the target file modified last time?
                  target_last_modified = \
                      self.storage.modified_time(prefixed_path)
              except (OSError, NotImplementedError, AttributeError):
                  # The storage doesn't support ``modified_time`` or failed
                  pass
              else:
                  try:
                      # When was the source file modified last time?
                      source_last_modified = source_storage.modified_time(path)
                  except (OSError, NotImplementedError, AttributeError):
                      pass
                  else:
                      # The full path of the target file
                      if self.local:
                          full_path = self.storage.path(prefixed_path)
                      else:
                          full_path = None
                      # Skip the file if the source file is younger
                      # Avoid sub-second precision (see #14665, #19540)
                      if (target_last_modified.replace(microsecond=0)
                              >= source_last_modified.replace(microsecond=0)):
                          if not ((self.symlink and full_path
                                   and not os.path.islink(full_path)) or
                                  (not self.symlink and full_path
                                   and os.path.islink(full_path))):
                              if prefixed_path not in self.unmodified_files:
                                  self.unmodified_files.append(prefixed_path)
                              self.log("Skipping '%s' (not modified)" % path)
                              return False
              # Then delete the existing file if really needed
              if self.dry_run:
                  self.log("Pretending to delete '%s'" % path)
              else:
                  self.log("Deleting '%s'" % path)
                  self.storage.delete(prefixed_path)
          return True
docs: Checks if the target file should be deleted if it already exists