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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(self, **kwargs):
 # pragma: no cover """Calls the TimeZoneField's custom checks."""


        errors = super(TimeZoneField, self).check(**kwargs)
        errors.extend(self._check_timezone_max_length_attribute())
        errors.extend(self._check_choices_attribute())
        return errors