'register a `CMAEvolutionStrategy` instance for logging,
``append=True`` appends to previous data logged under the same name,
by default previous data are overwritten.'

def register(self, es, append=None, modulo=None):

    if (type(es) != CMAEvolutionStrategy):
        raise TypeError('only    class    CMAEvolutionStrategy    can    be    registered    for    logging')
    self.es = es
    if (append is not None):
        self.append = append
    if (modulo is not None):
        self.modulo = modulo
    if ((not self.append) and (self.modulo != 0)):
        self.initialize()
    self.registered = True
    return self
