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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 locale(self) -> babel.core.Locale or None: """ Get user's locale :return: :class:`babel.core.Locale` """

        if not self.language_code:
            return None
        if not hasattr(self, '_locale'):
            setattr(self, '_locale', babel.core.Locale.parse(self.language_code, sep='-'))
        return getattr(self, '_locale')