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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 open_(environment, opts):
 # pylint: disable=unused-argument """Open web browser window to this environment Usage: datacats open [-r] [-s NAME] [ENVIRONMENT] Options: -s --site=NAME Choose a site to open [default: primary] ENVIRONMENT may be an environment name or a path to an environment directory. Default: '.' """


    environment.require_data()
    addr = environment.web_address()
    if not addr:
        print "Site not currently running"
    else:
        webbrowser.open(addr)