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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 change_ssh_port():
 """ For security woven changes the default ssh port. """

    host = normalize(env.host_string)[1]

    after = env.port
    before = str(env.DEFAULT_SSH_PORT)
    

    host_string=join_host_strings(env.user,host,before)
    with settings(host_string=host_string, user=env.user):
        if env.verbosity:
            print env.host, "CHANGING SSH PORT TO: "+str(after)
        sed('/etc/ssh/sshd_config','Port '+ str(before),'Port '+str(after),use_sudo=True)
        if env.verbosity:
            print env.host, "RESTARTING SSH on",after

        sudo('/etc/init.d/ssh restart')
        return True