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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 conn_options(prs, conn):
 """Set options of connecting to TonicDNS API server Arguments: prs: parser object of argparse conn: dictionary of connection information """

    if conn.get('server') and conn.get('username') and conn.get('password'):
        prs.set_defaults(server=conn.get('server'),
                         username=conn.get('username'),
                         password=conn.get('password'))

    elif conn.get('server') and conn.get('username'):
        prs.set_defaults(server=conn.get('server'),
                         username=conn.get('username'))

    if conn.get('auto_update_soa'):
        prs.set_defaults(auto_update_soa=conn.get('auto_update_soa'))
    else:
        prs.set_defaults(auto_update_soa=False)

    if not conn.get('server'):
        set_option(prs, 'server')
    if not conn.get('username'):
        set_option(prs, 'username')
    if not conn.get('password'):
        set_option(prs, 'password')