code: def send(self, value):
          
          if not self.block and self._stdin is not None:
              self.writer.write("{}\n".format(value))
              return self
          else:
              raise TypeError(NON_BLOCKING_ERROR_MESSAGE)
docs: Send text to stdin. Can only be used on non blocking commands
  
          Args:
              value (str): the text to write on stdin
          Raises:
              TypeError: If command is blocking
          Returns:
              ShellCommand: return this ShellCommand instance for chaining