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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 json2pattern(s):
 """ Convert JSON format to a query pattern. Includes even mongo shell notation without quoted key names. """

    # make valid JSON by wrapping field names in quotes
    s, _ = re.subn(r'([{,])\s*([^,{\s\'"]+)\s*:', ' \\1 "\\2" : ', s)
    # handle shell values that are not valid JSON
    s = shell2json(s)
    # convert to 1 where possible, to get rid of things like new Date(...)
    s, n = re.subn(r'([:,\[])\s*([^{}\[\]"]+?)\s*([,}\]])', '\\1 1 \\3', s)
    # now convert to dictionary, converting unicode to ascii
    try:
        doc = json.loads(s, object_hook=_decode_pattern_dict)
        return json.dumps(doc, sort_keys=True, separators=(', ', ': '))
    except ValueError as ex:
        return None