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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 build_url(base_url, partial_url):
 """ Makes sure the URL is built properly. https://test.com/1/2/3 https://test.com/2/3 https://test.com/2/3' """

        if not base_url.endswith('/'):
            base_url += '/'
        if partial_url.startswith('/'):
            partial_url = partial_url[1:]

        return urlparse.urljoin(base_url, partial_url)