def generate_topology(self, vcpu_num, cores=<NUM_LIT:1>, threads=<NUM_LIT:1>):
return ET.Element(<EOL>'<STR_LIT>',<EOL>sockets=str(vcpu_num),<EOL>cores=str(cores),<EOL>threads=str(threads),<EOL>)<EOL>
Generate CPU <topology> XML child

Args:
    vcpu_num(str): number of virtual CPUs
    cores(int): number of cores
    threads(int): number of threads

Returns:
    lxml.etree.Element: topology XML element