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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 _check_equals(self):
 """ check for = in position 8, set attribute _has_equals """

        card_string = self['card_string']
        if len(card_string) < 9:
            self._has_equals = False
        elif card_string[8] == '=':
            self._has_equals = True
        else:
            self._has_equals = False