code: def check_real_value(f, x1, y1, x, exact=True):
      z1 = np.array([complex(x1, y1)])
      if exact:
          assert_equal(f(z1), x)
      else:
          assert_almost_equal(f(z1), x)
  
imports: import sys
  import platform
  import pytest
  import numpy
  import numpy._core._multiarray_umath
  from numpy.testing import assert_raises, assert_equal, assert_array_equal, assert_almost_equal, assert_array_max_ulp
label_desc: Use image node_id 1 for calling a global function with example usage: check_real_value(f, x1, y1, x, exact) without return types