» ./python.exe Lib/test/test_cmd.py -c
Traceback (most recent call last):
  File "/Users/sobolev/Desktop/cpython2/Lib/test/test_cmd.py", line 262, in <module>
    test_coverage('/tmp/cmd.cover')
  File "/Users/sobolev/Desktop/cpython2/Lib/test/test_cmd.py", line 252, in test_coverage
    trace = support.import_module('trace')
            ^^^^^^^^^^^^^^^^^^^^^
AttributeError: module 'test.support' has no attribute 'import_module'

def test_coverage(coverdir):
    from test.support import import_helper
    trace = import_helper.import_module('trace')
    tracer=trace.Trace(ignoredirs=[sys.base_prefix, sys.base_exec_prefix,],
                        trace=0, count=1)
    tracer.run('import unittest; unittest.main()')
    r=tracer.results()
    print("Writing coverage results...")
    r.write_results(show_missing=True, summary=True, coverdir=coverdir)

» ./python.exe -m test -T test_cmd    
Using random seed: 2974785131
0:00:00 load avg: 1.22 Run 1 test sequentially
0:00:00 load avg: 1.22 [1/1] test_cmd

== Tests result: SUCCESS ==

1 test OK.

Total duration: 78 ms
Total tests: run=3
Total test files: run=1/1
Result: SUCCESS
lines   cov%   module   (path)
...
  236    63%   cmd   (/Users/sobolev/Desktop/cpython2/Lib/cmd.py)
...