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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 makeCNBaseURL(url):
 """Attempt to create a valid CN BaseURL when one or more sections of the URL are missing."""

    o = urllib.parse.urlparse(url, scheme=d1_common.const.DEFAULT_CN_PROTOCOL)
    if o.netloc and o.path:
        netloc = o.netloc
        path = o.path
    elif o.netloc:
        netloc = o.netloc
        path = d1_common.const.DEFAULT_CN_PATH
    elif o.path:
        s = o.path.split('/', 1)
        netloc = s[0]
        if len(s) == 1:
            path = d1_common.const.DEFAULT_CN_PATH
        else:
            path = s[1]
    else:
        netloc = d1_common.const.DEFAULT_CN_HOST
        path = d1_common.const.DEFAULT_CN_PATH
    return urllib.parse.urlunparse(
        (o.scheme, netloc, path, o.params, o.query, o.fragment)
    )