def test_string_value(self):
     with pytest.raises(ValueError):
         fib('aoeu')
 def test_float_values(self):
     with pytest.raises(ValueError):
         fib(2.7)
 def test_n_equal_to_zero(self):
     assert fib(0) == 0
 def test_power_function_normal_values(self):
     assert fib(3) == 2
 def test_negative_value(self):
     with pytest.raises(ValueError):
         print(fib(-2))
 def test_none_value(self):
     with pytest.raises(TypeError):
         fib(None)