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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_db_prep_lookup(self, lookup_type, value, connection=None, prepared=None):
 """ Returns field's value prepared for database lookup. """

        ## convert to settings.TIME_ZONE
        if value.tzinfo is None:
            value = default_tz.localize(value)
        else:
            value = value.astimezone(default_tz)
        return super(LocalizedDateTimeField, self).get_db_prep_lookup(lookup_type, value, connection=connection, prepared=prepared)