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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _get_target(self):
 """ returns a callable with no arguments designed to be the target of a Subprocess """

        if None in [self._func, self._func_kwargs, self._func_kwargs, self._every_kwargs]:
            raise ValueError('You must call the .every() and .run() methods on every tab.')
        return self._loop