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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 urlunsplit (urlparts):
 """Same as urlparse.urlunsplit but with extra UNC path handling for Windows OS."""

    res = urlparse.urlunsplit(urlparts)
    if os.name == 'nt' and urlparts[0] == 'file' and '|' not in urlparts[2]:
        # UNC paths must have 4 slashes: 'file:////server/path'
        # Depending on the path in urlparts[2], urlparse.urlunsplit()
        # left only two or three slashes. This is fixed below
        repl = 'file://' if urlparts[2].startswith('//') else 'file:/'
        res = res.replace('file:', repl)
    return res