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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 format_endpoint(schema, addr, port, api_version):
 """Return a formatted keystone endpoint @param schema: http or https @param addr: ipv4/ipv6 host of the keystone service @param port: port of the keystone service @param api_version: 2 or 3 @returns a fully formatted keystone endpoint """

    return '{}://{}:{}/{}/'.format(schema, addr, port,
                                   get_api_suffix(api_version))