def pl_true_int_repr(clause, model={}):
 result = False
 for lit in clause:
  if (lit < 0):
   p = model.get((- lit))
   if (p is not None):
    p = (not p)
  else:
   p = model.get(lit)
  if (p is True):
   return True
  elif (p is None):
   result = None
 return result

def pl_true_int_repr ( clause , model = { } ) : result = False for lit in clause : if ( lit < 0 ) : p = model . get ( ( - lit ) ) if ( p is not None ) : p = ( not p ) else : p = model . get ( lit ) if ( p is True ) : return True elif ( p is None ) : result = None return result
lightweight version of pl_true .