code: def get_file(self, fp, headers=None, cb=None, num_cb=10, torrent=False):
          
          if self.key_type & self.KEY_STREAM_READABLE:
              raise BotoClientError('Stream is not Readable')
          elif self.key_type & self.KEY_STREAM_WRITABLE:
              key_file = self.fp
          else:
              key_file = open(self.full_path, 'rb')
          try:
              shutil.copyfileobj(key_file, fp)
          finally:
              key_file.close()
docs: Retrieves a file from a Key
  
          :type fp: file
          :param fp: File pointer to put the data into
  
          :type headers: string
          :param: ignored in this subclass.
  
          :type cb: function
          :param cb: ignored in this subclass.
  
          :type cb: int
          :param num_cb: ignored in this subclass.