mock is included in unittest since Python 3.3

https://docs.python.org/3/library/unittest.mock.html

"Pyt runs on python 3.6+":
609acd6#r29924039

Author: Daniel M. Capella

tests/main_test.py

@@ -1,4 +1,4 @@
-import mock
+from unittest import mock
 
 from .base_test_case import BaseTestCase
 from pyt.__main__ import discover_files, main

tox.ini

@@ -2,15 +2,13 @@
 envlist = py36,cover,lint
 
 [testenv]
-deps = mock
 commands =
     python -m tests
 
 [testenv:cover]
 whitelist_externals = coverage
 deps =
     coverage>=4.0,<4.4
-    mock
 commands =
     coverage erase
     coverage run tests