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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 quote_edge(identifier):
 """Return DOT edge statement node_id from string, quote if needed. 'spam' '"spam spam":"eggs eggs"' 'spam:eggs:s' """

    node, _, rest = identifier.partition(':')
    parts = [quote(node)]
    if rest:
        port, _, compass = rest.partition(':')
        parts.append(quote(port))
        if compass:
            parts.append(compass)
    return ':'.join(parts)