use the called property of the run_pip mock rather than an assertion method that doesn't exist

Lib/test/test_ensurepip.py

@@ -153,7 +153,7 @@ class TestBootstrap(EnsurepipMixin, unittest.TestCase):
     def test_altinstall_default_pip_conflict(self):
         with self.assertRaises(ValueError):
             ensurepip.bootstrap(altinstall=True, default_pip=True)
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
 
     @requires_usable_pip
     def test_pip_environment_variables_removed(self):
@@ -194,7 +194,7 @@ class TestUninstall(EnsurepipMixin, unittest.TestCase):
     def test_uninstall_skipped_when_not_installed(self):
         with fake_pip(None):
             ensurepip._uninstall_helper()
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
 
     def test_uninstall_skipped_with_warning_for_wrong_version(self):
         with fake_pip("not a valid version"):
@@ -202,7 +202,7 @@ class TestUninstall(EnsurepipMixin, unittest.TestCase):
                 ensurepip._uninstall_helper()
         warning = stderr.getvalue().strip()
         self.assertIn("only uninstall a matching version", warning)
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
 
 
     @requires_usable_pip
@@ -272,7 +272,7 @@ class TestMissingSSL(EnsurepipMixin, unittest.TestCase):
         self.os_environ["PIP_THIS_SHOULD_STAY"] = "test fodder"
         with self.assertRaisesRegex(RuntimeError, "requires SSL/TLS"):
             ensurepip_no_ssl.bootstrap()
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
         self.assertIn("PIP_THIS_SHOULD_STAY", self.os_environ)
 
     def test_uninstall_requires_ssl(self):
@@ -280,7 +280,7 @@ class TestMissingSSL(EnsurepipMixin, unittest.TestCase):
         with self.assertRaisesRegex(RuntimeError, "requires SSL/TLS"):
             with fake_pip():
                 ensurepip_no_ssl._uninstall_helper()
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
         self.assertIn("PIP_THIS_SHOULD_STAY", self.os_environ)
 
     def test_main_exits_early_with_warning(self):
@@ -288,7 +288,7 @@ class TestMissingSSL(EnsurepipMixin, unittest.TestCase):
             ensurepip_no_ssl._main(["--version"])
         warning = stderr.getvalue().strip()
         self.assertTrue(warning.endswith("requires SSL/TLS"), warning)
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
 
 # Basic testing of the main functions and their argument parsing
 
@@ -303,7 +303,7 @@ class TestBootstrappingMainFunction(EnsurepipMixin, unittest.TestCase):
                 ensurepip._main(["--version"])
         result = stdout.getvalue().strip()
         self.assertEqual(result, EXPECTED_VERSION_OUTPUT)
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
 
     @requires_usable_pip
     def test_basic_bootstrapping(self):
@@ -328,7 +328,7 @@ class TestUninstallationMainFunction(EnsurepipMixin, unittest.TestCase):
                 ensurepip._uninstall._main(["--version"])
         result = stdout.getvalue().strip()
         self.assertEqual(result, EXPECTED_VERSION_OUTPUT)
-        self.run_pip.assert_not_called()
+        self.assertFalse(self.run_pip.called)
 
     @requires_usable_pip
     def test_basic_uninstall(self):