python · terryjreedy · Sep 4, 2021 · Aug 31, 2021
diff --git a/Doc/library/dbm.rst b/Doc/library/dbm.rst
@@ -216,7 +216,7 @@ supported.
       contains them all::
 
          k = db.firstkey()
-         while k != None:
+         while k is not None:
              print(k)
              k = db.nextkey(k)
 

diff --git a/Lib/ctypes/_aix.py b/Lib/ctypes/_aix.py
@@ -282,7 +282,7 @@ def find_shared(paths, name):
         if path.exists(archive):
             members = get_shared(get_ld_headers(archive))
             member = get_member(re.escape(name), members)
-            if member != None:
+            if member is not None:
                 return (base, member)
             else:
                 return (None, None)
@@ -307,7 +307,7 @@ def find_library(name):
 
     libpaths = get_libpaths()
     (base, member) = find_shared(libpaths, name)
-    if base != None:
+    if base is not None:
         return f"{base}({member})"
 
     # To get here, a member in an archive has not been found

@@ -144,7 +144,7 @@ def _encode_text(string, charset, cte, policy):
     linesep = policy.linesep.encode('ascii')
     def embedded_body(lines): return linesep.join(lines) + linesep
     def normal_body(lines): return b'\n'.join(lines) + b'\n'
-    if cte==None:
+    if cte is None:
         # Use heuristics to decide on the "best" encoding.
         if max((len(x) for x in lines), default=0) <= policy.max_line_length:
             try:

@@ -344,7 +344,7 @@ def test_comparison(self):
         with self.assertRaises(TypeError): timezone(ZERO) < timezone(ZERO)
         self.assertIn(timezone(ZERO), {timezone(ZERO)})
         self.assertTrue(timezone(ZERO) != None)
-        self.assertFalse(timezone(ZERO) ==  None)
+        self.assertFalse(timezone(ZERO) == None)
 
         tz = timezone(ZERO)
         self.assertTrue(tz == ALWAYS_EQ)

diff --git a/Lib/test/test_pty.py b/Lib/test/test_pty.py
@@ -136,7 +136,7 @@ def test_openpty(self):
             mode = None
 
         new_stdin_winsz = None
-        if self.stdin_rows != None and self.stdin_cols != None:
+        if self.stdin_rows is not None and self.stdin_cols is not None:
             try:
                 # Modify pty.STDIN_FILENO window size; we need to
                 # check if pty.openpty() is able to set pty slave

diff --git a/Lib/test/test_type_annotations.py b/Lib/test/test_type_annotations.py
@@ -71,7 +71,7 @@ def __annotations__(self, value):
 
             @__annotations__.deleter
             def __annotations__(self):
-                if hasattr(self, 'my_annotations') and self.my_annotations == None:
+                if getattr(self, 'my_annotations', False) is None:
                     raise AttributeError('__annotations__')
                 self.my_annotations = None
 

diff --git a/Modules/_gdbmmodule.c b/Modules/_gdbmmodule.c
@@ -450,15 +450,15 @@ The following code prints every key in the database db, without having
 to create a list in memory that contains them all:
 
       k = db.firstkey()
-      while k != None:
+      while k is not None:
           print(k)
           k = db.nextkey(k)
 [clinic start generated code]*/
 
 static PyObject *
 _gdbm_gdbm_nextkey_impl(gdbmobject *self, PyTypeObject *cls, const char *key,
                         Py_ssize_clean_t key_length)
-/*[clinic end generated code: output=204964441fdbaf02 input=fcf6a51a96ce0172]*/
+/*[clinic end generated code: output=204964441fdbaf02 input=365e297bc0b3db48]*/
 {
     PyObject *v;
     datum dbm_key, nextkey;

diff --git a/Modules/clinic/_gdbmmodule.c.h b/Modules/clinic/_gdbmmodule.c.h
diff --git a/Tools/clinic/clinic.py b/Tools/clinic/clinic.py
@@ -1632,7 +1632,7 @@ def print_block(self, block):
         dsl_name = block.dsl_name
         write = self.f.write
 
-        assert not ((dsl_name == None) ^ (output == None)), "you must specify dsl_name and output together, dsl_name " + repr(dsl_name)
+        assert not ((dsl_name is None) ^ (output is None)), "you must specify dsl_name and output together, dsl_name " + repr(dsl_name)
 
         if not dsl_name:
             write(input)
@@ -2931,7 +2931,7 @@ def converter_init(self, *, accept={int}, type=None):
             self.format_unit = 'C'
         elif accept != {int}:
             fail("int_converter: illegal 'accept' argument " + repr(accept))
-        if type != None:
+        if type is not None:
             self.type = type
 
     def parse_arg(self, argname, displayname):