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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 init_command(default_output_format, default_myproxy_username):
 """ Executor for `globus config init` """

    # now handle the output format, requires a little bit more care
    # first, prompt if it isn't given, but be clear that we have a sensible
    # default if they don't set it
    # then, make sure that if it is given, it's a valid format (discard
    # otherwise)
    # finally, set it only if given and valid
    if not default_output_format:
        safeprint(
            textwrap.fill(
                'This must be one of "json" or "text". Other values will be '
                "ignored. ENTER to skip."
            )
        )
        default_output_format = (
            click.prompt(
                "Default CLI output format (cli.output_format)", default="text"
            )
            .strip()
            .lower()
        )
        if default_output_format not in ("json", "text"):
            default_output_format = None

    if not default_myproxy_username:
        safeprint(textwrap.fill("ENTER to skip."))
        default_myproxy_username = click.prompt(
            "Default myproxy username (cli.default_myproxy_username)",
            default="",
            show_default=False,
        ).strip()

    # write to disk
    safeprint(
        "\n\nWriting updated config to {0}".format(os.path.expanduser("~/.globus.cfg"))
    )
    write_option(OUTPUT_FORMAT_OPTNAME, default_output_format)
    write_option(MYPROXY_USERNAME_OPTNAME, default_myproxy_username)