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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 __valid_url(cls, url):
 """Expects input to already be a valid string"""

        bits = urlparse(url)
        return ((bits.scheme == "http" or bits.scheme == "https") and
                _PATTERN_URL_PART.match(bits.netloc) and
                _PATTERN_URL_PART.match(bits.path))