bpo-26985: Add missing info of code object in inspect documentation (GH-1090) (GH-1099)

diff --git a/Lib/inspect.py b/Lib/inspect.py
index 4d56ef5..a2dcb88 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -253,18 +253,24 @@
     """Return true if the object is a code object.
 
     Code objects provide these attributes:
-        co_argcount     number of arguments (not including * or ** args)
-        co_code         string of raw compiled bytecode
-        co_consts       tuple of constants used in the bytecode
-        co_filename     name of file in which this code object was created
-        co_firstlineno  number of first line in Python source code
-        co_flags        bitmap: 1=optimized | 2=newlocals | 4=*arg | 8=**arg
-        co_lnotab       encoded mapping of line numbers to bytecode indices
-        co_name         name with which this code object was defined
-        co_names        tuple of names of local variables
-        co_nlocals      number of local variables
-        co_stacksize    virtual machine stack space required
-        co_varnames     tuple of names of arguments and local variables"""
+        co_argcount         number of arguments (not including *, ** args
+                            or keyword only arguments)
+        co_code             string of raw compiled bytecode
+        co_cellvars         tuple of names of cell variables
+        co_consts           tuple of constants used in the bytecode
+        co_filename         name of file in which this code object was created
+        co_firstlineno      number of first line in Python source code
+        co_flags            bitmap: 1=optimized | 2=newlocals | 4=*arg | 8=**arg
+                            | 16=nested | 32=generator | 64=nofree | 128=coroutine
+                            | 256=iterable_coroutine | 512=async_generator
+        co_freevars         tuple of names of free variables
+        co_kwonlyargcount   number of keyword only arguments (not including ** arg)
+        co_lnotab           encoded mapping of line numbers to bytecode indices
+        co_name             name with which this code object was defined
+        co_names            tuple of names of local variables
+        co_nlocals          number of local variables
+        co_stacksize        virtual machine stack space required
+        co_varnames         tuple of names of arguments and local variables"""
     return isinstance(object, types.CodeType)
 
 def isbuiltin(object):