code: def set_content(self, value: RequestContent, *,
                      content_type: str = None):
          '''
          Sets the content of the request.
          '''
          assert self._attached_files is None, \
                 'cannot set content because you already attached files.'
          guessed_content_type = 'application/octet-stream'
          if value is None:
              guessed_content_type = 'text/plain'
              self._content = b''
          elif isinstance(value, str):
              guessed_content_type = 'text/plain'
              self._content = value.encode('utf-8')
          else:
              guessed_content_type = 'application/octet-stream'
              self._content = value
          self.content_type = (content_type if content_type is not None
                               else guessed_content_typef set_content(self, value: RequestContent, *,
                      content_type: str = None):
          '''
          Sets the content of the request.
          '''
          assert self._attached_files is None, \
                 'cannot set content because you already attached files.'
          guessed_content_type = 'application/octet-stream'
          if value is None:
              guessed_content_type = 'text/plain'
              self._content = b''
          elif isinstance(value, str):
              guessed_content_type = 'text/plain'
              self._content = value.encode('utf-8')
          else:
              guessed_content_type = 'application/octet-stream'
              self._content = value
          self.content_type = (content_type if content_type is not None
                               else guessed_content_type)
docs: Sets the content of the request.