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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 _normalize_tags(self, tags):
        '''
        Coerces tags to lowercase strings

        Parameters
        ----------
        tags: list or tuple of strings

        '''

        lowered_str_tags = []
        for tag in tags:
            lowered_str_tags.append(str(tag).lower())

        return lowered_str_tags