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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 normalize_url(node):
 """Normalizes the given node url"""

    if not node:
        node = DEFAULT_NODE
    elif '://' not in node:
        node = '//{}'.format(node)
    parts = urlparse(node, scheme='http', allow_fragments=False)
    port = parts.port if parts.port else _get_default_port(parts.scheme)
    netloc = '{}:{}'.format(parts.hostname, port)
    return urlunparse((parts.scheme, netloc, parts.path, '', '', ''))