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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 _have_cache_for_date(self, dt):
 """ Return True if we have cached data for all projects for the specified datetime. Return False otherwise. :param dt: datetime to find cache for :type dt: datetime.datetime :return: True if we have cache for all projects for this date, False otherwise :rtype: bool """

        for p in self.projects:
            if self.cache.get(p, dt) is None:
                return False
        return True