for i in n:

  temp_aut = spot.automaton(aut.to_str()) # copy an automaton

  ...something

  del temp_aut

But I found that whenever it enters a new loop, the memory of the automaton assigned to temp_aut is not freed. And it leads to a memory overflow. 

I thought this might be solved with 'delete temp_aut' in the C++ version spot, but in the python interface 'del temp' doesn't seem to work. 

Is there any interface in Python or other operations to make it possible?