text: from sympy.sets import ConditionSet
  from sympy import (Symbol, Eq, S, sin, pi, Lambda, Interval)
  
  x = Symbol('x')
  
  
  def test_CondSet():
      sin_sols_principal = ConditionSet(Lambda(x, Eq(sin(x), 0)),
                                        Interval(0, 2*pi, False, True))
      assert pi in sin_sols_principal
      assert pi/2 not in sin_sols_principal
      assert 3*pi not in sin_sols_principal
      assert 5 in ConditionSet(Lambda(x, x**2 > 4), S.Reals)
      assert 1 not in ConditionSet(Lambda(x, x**2 > 4), S.Reals)
  