code: def test_to_fortran(self):
      f = [IntFormat(10), IntFormat(12, 10), IntFormat(12, 10, 3)]
      res = ["(I10)", "(I12.10)", "(3I12.10)"]
  
      for i, j in zip(f, res):
          assert_equal(i.fortran_format, j)
  
file_path: scipy/scipy/io/_harwell_boeing/tests/test_fortran_format.py
imports: import numpy
  from numpy.testing import assert_equal
  from pytest import raises
  from scipy.io._harwell_boeing import FortranFormatParser, IntFormat, ExpFormat, BadFortranFormat
label_desc: Use image node_id 1 for calling the TestIntFormat obj's underlying member method code with example usage: obj.test_to_fortran() without return types