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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 browse_home_listpage_url(self, state=None, county=None, zipcode=None, street=None, **kwargs):
 """ Construct an url of home list page by state, county, zipcode, street. Example: - https://www.zillow.com/browse/homes/ca/ - https://www.zillow.com/browse/homes/ca/los-angeles-county/ - https://www.zillow.com/browse/homes/ca/los-angeles-county/91001/ - https://www.zillow.com/browse/homes/ca/los-angeles-county/91001/tola-ave_5038895/ """

        url = self.domain_browse_homes
        for item in [state, county, zipcode, street]:
            if item:
                url = url + "/%s" % item
        url = url + "/"
        return url