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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_context(awsclient, env, tool, command, arguments=None):
 """This assembles the tool context. Private members are preceded by a '_'. :param tool: :param command: :return: dictionary containing the gcdt tool context """

    # TODO: elapsed, artifact(stack, depl-grp, lambda, api)
    if arguments is None:
        arguments = {}
    context = {
        '_awsclient': awsclient,
        'env': env,
        'tool': tool,
        'command': command,
        '_arguments': arguments,  # TODO clean up arguments -> args
        'version': __version__,
        'user': _get_user(),
        'plugins': get_plugin_versions().keys()
    }

    return context