<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_nowait(self, name, default=_MISSING, autoremove=False):
 """Get the value of a key if it is already set. This method allows you to check if a key has already been set without blocking. If the key has not been set you will get the default value you pass in or KeyError() if no default is passed. When this method returns the key is automatically removed unless you pass ``autoremove=False``. This method is not a coroutine and does not block. Args: name (str):
 The name of the key to wait on. default (object):
 The default value to return if the key has not yet been set. Defaults to raising KeyError(). autoremove (bool):
 Whether to automatically remove the key when get() returns. Returns: object: Whatever was set in the key by :meth:`set`. """


        self._ensure_declared(name)

        try:
            future = self._data[name]
            if future.done():
                return future.result()

            if default is _MISSING:
                raise KeyError("Key {} has not been assigned a value and no default given".format(name))

            return default
        finally:
            if autoremove:
                self._data[name].cancel()
                del self._data[name]