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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 path_to_pattern(api_path, parameters):
 """ Given an api path, possibly with parameter notation, return a pattern suitable for turing into a regular expression which will match request paths that conform to the parameter definitions and the api path. """

    parts = re.split(PARAMETER_REGEX, api_path)
    pattern = ''.join((process_path_part(part, parameters) for part in parts))

    if not pattern.startswith('^'):
        pattern = "^{0}".format(pattern)
    if not pattern.endswith('$'):
        pattern = "{0}$".format(pattern)

    return pattern