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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 _check_user_parameters(self, user_parameters):
 """ Verifies that the parameter dict given by the user only contains known keys. This ensures that the user detects typos faster. """

        if not user_parameters:
            return

        # sanity check against typos
        for key in user_parameters:
            if key not in submission_defaults:
                raise ValueError("Unknown parameter {0}".format(key))