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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 set_env_var(key: str, value: str):
 """ Sets environment variable on AV Args: key: variable name value: variable value """

        elib_run.run(f'appveyor SetVariable -Name {key} -Value {value}')
        AV.info('Env', f'set "{key}" -> "{value}"')