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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 validate_keys(self, *keys):
 """Validation helper to ensure that keys are present in data This method makes sure that all of keys received here are present in the data received from the caller. It is better to call this method in the `validate()` method of your event. Not in the `clean()` one, since the first will be called locally, making it easier to debug things and find problems. """

        current_keys = set(self.data.keys())
        needed_keys = set(keys)
        if not needed_keys.issubset(current_keys):
            raise ValidationError(
                'One of the following keys are missing from the '
                'event\'s data: {}'.format(
                    ', '.join(needed_keys.difference(current_keys)))
            )
        return True