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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_house_number(self, token):
 """ Attempts to find a house number, generally the first thing in an address. If anything is in front of it, we assume it is a building name. """

        if self.street and self.house_number is None and re.match(street_num_regex, token.lower()):
            if '/' in token:
                token = token.split('/')[0]
            if '-' in token:
                token = token.split('-')[0]
            self.house_number = self._clean(str(token))
            return True
        return False