in theseus/core/cost_function.py [0:0]
def _register_vars_in_list(var_list_, is_optim=False):
for var_ in var_list_:
if hasattr(self, var_.name):
raise RuntimeError(f"Variable name {var_.name} is not allowed.")
setattr(self, var_.name, var_)
if is_optim:
self.register_optim_var(var_.name)
else:
self.register_aux_var(var_.name)