code: def recv(self):
          
          with self.readlock:
              opcode, data = self.recv_data()
          if six.PY3 and opcode == ABNF.OPCODE_TEXT:
              return data.decode("utf-8")
          elif opcode == ABNF.OPCODE_TEXT or opcode == ABNF.OPCODE_BINARY:
              return data
          else:
              return ''
docs: Receive string data(byte array) from the server.
  
          return value: string(byte array) value.