code: def test_main_microseconds(self):
      s = self.run_main(
          seconds_per_increment=0.0000025, switches=["-n100"]
      )
      self.assertEqual(s, "100 loops, best of 5: 2.5 usec per loop\n")
  
imports: import timeit
  import unittest
  import sys
  import io
  from textwrap import dedent
  from test.support import captured_stdout
  from test.support import captured_stderr
label_desc: Use image node_id 34 for calling the TestTimeit obj's underlying member method code with example usage: obj.test_main_microseconds() without return types