code: def test_empty_cnf():
      cnf = CNF()
      enc = EncodedCNF()
      enc.from_cnf(cnf)
      lra, conflict = LRASolver.from_encoded_cnf(enc)
      assert len(conflict) == 0
      assert lra.check() == (True, {})
  
imports: from sympy.core.numbers import Rational, I, oo
  from sympy.core.relational import Eq
  from sympy.core.symbol import symbols
  from sympy.core.singleton import S
  from sympy.matrices.dense import Matrix
  from sympy.matrices.dense import randMatrix
  from sympy.assumptions.ask import Q
  from sympy.logic.boolalg import And
  from sympy.abc import x, y, z
  from sympy.assumptions.cnf import CNF, EncodedCNF
  from sympy.functions.elementary.trigonometric import cos
  from sympy.external import import_module
  from sympy.logic.algorithms.lra_theory import LRASolver, UnhandledInput, LRARational, HANDLE_NEGATION
  from sympy.core.random import random, choice, randint
  from sympy.core.sympify import sympify
  from sympy.ntheory.generate import randprime
  from sympy.core.relational import StrictLessThan, StrictGreaterThan
  import itertools
  from sympy.testing.pytest import raises, XFAIL, skip
label_desc: Use image node_id 16 for calling a global function with example usage: test_empty_cnf() without return types