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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_hours_description(self):
 """Generates a description for only the HOUR portion of the expression Returns: The HOUR description """

        expression = self._expression_parts[2]
        return self.get_segment_description(
            expression,
            _("every hour"),
            lambda s: self.format_time(s, "0"),
            lambda s: _("every {0} hours").format(s),
            lambda s: _("between {0} and {1}"),
            lambda s: _("at {0}")
        )