code: def _parse_integrator(int_method):
      
      #Pick integrator
      if int_method.lower() == 'rk4_c':
          int_method_c= 1
      elif int_method.lower() == 'rk6_c':
          int_method_c= 2
      elif int_method.lower() == 'symplec4_c':
          int_method_c= 3
      elif int_method.lower() == 'symplec6_c':
          int_method_c= 4
      elif int_method.lower() == 'dopr54_c':
          int_method_c= 5
      elif int_method.lower() == 'dop853_c':
          int_method_c= 6
      else:
          int_method_c= 0
      return int_method_c
docs: parse the integrator method to pass to C