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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 file_uri(fname):

 """Select the right file uri scheme according to the operating system"""

    if os.name == 'nt':
        # Local file
        if re.search(r'^[a-zA-Z]:', fname):
            return 'file:///' + fname
        # UNC based path
        else:
            return 'file://' + fname
    else:
        return 'file://' + fname