def save_config(config):
    """Save configuration file to users data location.

     - Linux: ~/.local/share/pyfilemail
     - OSX: ~/Library/Application Support/pyfilemail
     - Windows: C:\\\Users\\\{username}\\\AppData\\\Local\\\pyfilemail

     :rtype: str
    """

    configfile = get_configfile()

    if not os.path.exists(configfile):
        configdir = os.path.dirname(configfile)

        if not os.path.exists(configdir):
            os.makedirs(configdir)

    data = config

    with open(configfile, 'wb') as f:
        json.dump(data, f, indent=2)
Save configuration file to users data location.

     - Linux: ~/.local/share/pyfilemail
     - OSX: ~/Library/Application Support/pyfilemail
     - Windows: C:\\\Users\\\{username}\\\AppData\\\Local\\\pyfilemail

     :rtype: str