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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 instance_path_for(name, identifier_type, identifier_key=None):
 """ Get a path for thing. """

    return "/{}/<{}:{}>".format(
        name_for(name),
        identifier_type,
        identifier_key or "{}_id".format(name_for(name)),
    )