code: def single_fact_lookup(known_facts_keys, known_facts_cnf):
      # Return the dictionary for quick lookup of single fact
      mapping = {}
      for key in known_facts_keys:
          mapping[key] = {key}
          for other_key in known_facts_keys:
              if other_key != key:
                  if ask_full_inference(
                      other_key, key, known_facts_cnf
                  ):
                      mapping[key].add(other_key)
                  if ask_full_inference(
                      ~other_key, key, known_facts_cnf
                  ):
                      mapping[key].add(~other_key)
      return mapping
  
file_path: sympy/sympy/assumptions/facts.py
imports: from sympy.assumptions.ask import Q
  from sympy.assumptions.assume import AppliedPredicate
  from sympy.core.cache import cacheit
  from sympy.core.symbol import Symbol
  from sympy.logic.boolalg import to_cnf, And, Not, Implies, Equivalent, Exclusive
  from sympy.logic.inference import satisfiable
label_desc: Use image node_id 7 for calling a global function with example usage: single_fact_lookup(known_facts_keys, known_facts_cnf) and returns: mapping