def check_and_load_ssh_auth():
mac_username = get_config_value(constants.CONFIG_MAC_USERNAME_KEY)<EOL>if not mac_username:<EOL><INDENT>logging.info("<STR_LIT>")<EOL>return<EOL><DEDENT>if not _running_on_mac(): <EOL><INDENT>logging.info("<STR_LIT>")<EOL>return<EOL><DEDENT>if _mac_version_is_post_yosemite():<EOL><INDENT>_load_ssh_auth_post_yosemite(mac_username)<EOL><DEDENT>else:<EOL><INDENT>_load_ssh_auth_pre_yosemite()<EOL><DEDENT>
Will check the mac_username config value; if it is present, will load that user's
SSH_AUTH_SOCK environment variable to the current environment.  This allows git clones
to behave the same for the daemon as they do for the user