description = "This example script will REGISTER using the specified credentials and either sit idle waiting for an incoming audio call, or attempt to make an outgoing audio call to the specified target. The program will close the session and quit when CTRL+D is pressed."
parser.add_option("-e", "--expires", type="int", dest="expires", help='"Expires" value to set in REGISTER. Default is 300 seconds.')
parser.add_option("-p", "--outbound-proxy", type="string", action="callback", callback=lambda option, opt_str, value, parser: parse_host_port(option, opt_str, value, parser, "proxy_ip", "proxy_port", 5060), help="Outbound SIP proxy to use. By default a lookup is performed based on SRV and A records.", metavar="IP[:PORT]")
parser.add_option("-s", "--do-sip-trace", action="store_true", dest="do_siptrace", help="Dump the raw contents of incoming and outgoing SIP messages (disabled by default).")
parser.add_option("-n", "--no-register", action="store_false", dest="do_register", help="Do not perform a REGISTER before starting and outgoing session (enabled by default).")