code: def test_offset_read(self):
      self.tempfile()
      self.run_test(
          """
              def _offset_read(filename):
                  f = open(filename)
                  f.seek(5)
                  c = f.read()
                  f.close()
                  return c""",
          self.filename,
          _offset_read=[str],
      )
  
imports: from tempfile import mkstemp
  from pythran.tests import TestEnv
  import unittest
  from pythran.typing import List
label_desc: Use image node_id 19 for calling the TestFile obj's underlying member method code with example usage: obj.test_offset_read() without return types