#!python

from gevent import monkey; monkey.patch_all()
from gevent.threadpool import ThreadPool
import unittest

class ThreadPoolTests(unittest.TestCase):
    def executor(self):
        print('I ran in a real thread!')
        return 123

    def test_threadpool(self):
        pool = ThreadPool(10)
        print(pool.spawn(self.executor).get())
        pool.kill()

if __name__ == '__main__':
    unittest.main()

$ coverage run --concurrency=gevent test_threadpool.py && coverage report -m
I ran in a real thread!
123
.
----------------------------------------------------------------------
Ran 1 test in 0.003s

OK
Name                 Stmts   Miss  Cover   Missing
--------------------------------------------------
test_threadpool.py      13      2    85%   7-8

$ coverage --version
Coverage.py, version 4.5.1 with C extension
Documentation at https://coverage.readthedocs.io
$ python --version
Python 3.6.5 :: Anaconda, Inc.
$ python -c "import gevent; print(gevent.__version__)"
1.3.3