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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_param(name, ns):
 """ Build a path parameter definition. """

    if ns.identifier_type == "uuid":
        param_type = "string"
        param_format = "uuid"
    else:
        param_type = "string"
        param_format = None

    kwargs = {
        "name": name,
        "in": "path",
        "required": True,
        "type": param_type,
    }
    if param_format:
        kwargs["format"] = param_format
    return swagger.PathParameterSubSchema(**kwargs)