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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 get_client_settings_env(**_):
 """Retrieve client settings from environment settings. :param \\*\\*kwargs: Arguments that are passed into the client instance """


    return {
        'proxy': os.environ.get('https_proxy'),
        'username': os.environ.get('SL_USERNAME'),
        'api_key': os.environ.get('SL_API_KEY'),
    }