Various small fixes to dis docs (#103923)

- Fix description of MAKE_CELL, which appeared to be inverted from the
  actual behavior
- Fix stray ".:" (sphinx-contrib/sphinx-lint#63)
- Fix inconsistent indentation
- Add some missing code blocks
- Slight style improvements

Doc/library/dis.rst

@@ -402,7 +402,7 @@ The Python compiler currently generates the following bytecode instructions.
 
 **General instructions**
 
-In the following, We will refer to the interpreter stack as STACK and describe
+In the following, We will refer to the interpreter stack as ``STACK`` and describe
 operations on it as if it was a Python list. The top of the stack corresponds to
 ``STACK[-1]`` in this language.
 
@@ -414,7 +414,7 @@ operations on it as if it was a Python list. The top of the stack corresponds to
 
 .. opcode:: POP_TOP
 
-   Removes the top-of-stack item.::
+   Removes the top-of-stack item::
 
       STACK.pop()
 
@@ -422,7 +422,7 @@ operations on it as if it was a Python list. The top of the stack corresponds to
 .. opcode:: END_FOR
 
    Removes the top two values from the stack.
-   Equivalent to POP_TOP; POP_TOP.
+   Equivalent to ``POP_TOP``; ``POP_TOP``.
    Used to clean up at the end of loops, hence the name.
 
    .. versionadded:: 3.12
@@ -431,7 +431,7 @@ operations on it as if it was a Python list. The top of the stack corresponds to
 .. opcode:: COPY (i)
 
    Push the i-th item to the top of the stack without removing it from its original
-   location.::
+   location::
 
       assert i > 0
       STACK.append(STACK[-i])
@@ -441,7 +441,7 @@ operations on it as if it was a Python list. The top of the stack corresponds to
 
 .. opcode:: SWAP (i)
 
-   Swap the top of the stack with the i-th element.::
+   Swap the top of the stack with the i-th element::
 
       STACK[-i], STACK[-1] = stack[-1], STACK[-i]
 
@@ -513,7 +513,7 @@ not have to be) the original ``STACK[-2]``.
 .. opcode:: BINARY_OP (op)
 
    Implements the binary and in-place operators (depending on the value of
-   *op*).::
+   *op*)::
 
       rhs = STACK.pop()
       lhs = STACK.pop()
@@ -580,14 +580,14 @@ not have to be) the original ``STACK[-2]``.
 
    Implements ``STACK[-1] = get_awaitable(STACK[-1])``, where ``get_awaitable(o)``
    returns ``o`` if ``o`` is a coroutine object or a generator object with
-   the CO_ITERABLE_COROUTINE flag, or resolves
+   the :data:`~inspect.CO_ITERABLE_COROUTINE` flag, or resolves
    ``o.__await__``.
 
     If the ``where`` operand is nonzero, it indicates where the instruction
     occurs:
 
-    * ``1`` After a call to ``__aenter__``
+    * ``1``: After a call to ``__aenter__``
-    * ``2`` After a call to ``__aexit__``
+    * ``2``: After a call to ``__aexit__``
 
    .. versionadded:: 3.5
 
@@ -652,6 +652,7 @@ not have to be) the original ``STACK[-2]``.
 .. opcode:: SET_ADD (i)
 
    Implements::
+
       item = STACK.pop()
       set.add(STACK[-i], item)
 
@@ -751,7 +752,7 @@ iterations of the loop.
 .. opcode:: CHECK_EXC_MATCH
 
    Performs exception matching for ``except``. Tests whether the ``STACK[-2]``
-   is an exception matching ``STACK[-1]``. Pops STACK[-1] and pushes the boolean
+   is an exception matching ``STACK[-1]``. Pops ``STACK[-1]`` and pushes the boolean
    result of the test.
 
    .. versionadded:: 3.11
@@ -863,7 +864,7 @@ iterations of the loop.
 .. opcode:: UNPACK_SEQUENCE (count)
 
    Unpacks ``STACK[-1]`` into *count* individual values, which are put onto the stack
-   right-to-left.::
+   right-to-left::
 
       STACK.extend(STACK.pop()[:count:-1])
 
@@ -1028,7 +1029,7 @@ iterations of the loop.
    This bytecode distinguishes two cases: if ``STACK[-1]`` has a method with the
    correct name, the bytecode pushes the unbound method and ``STACK[-1]``.
    ``STACK[-1]`` will be used as the first argument (``self``) by :opcode:`CALL`
-   when calling the unbound method. Otherwise, ``NULL`` and the object return by
+   when calling the unbound method. Otherwise, ``NULL`` and the object returned by
    the attribute lookup are pushed.
 
    .. versionchanged:: 3.12
@@ -1207,7 +1208,7 @@ iterations of the loop.
 
 .. opcode:: MAKE_CELL (i)
 
-   Creates a new cell in slot ``i``.  If that slot is empty then
+   Creates a new cell in slot ``i``.  If that slot is nonempty then
    that value is stored into the new cell.
 
    .. versionadded:: 3.11
@@ -1521,7 +1522,7 @@ iterations of the loop.
 
 **Pseudo-instructions**
 
-These opcodes do not appear in python bytecode, they are used by the compiler
+These opcodes do not appear in Python bytecode. They are used by the compiler
 but are replaced by real opcodes or removed before bytecode is generated.
 
 .. opcode:: SETUP_FINALLY (target)
@@ -1533,7 +1534,7 @@ but are replaced by real opcodes or removed before bytecode is generated.
 
 .. opcode:: SETUP_CLEANUP (target)
 
-   Like ``SETUP_FINALLY``, but in case of exception also pushes the last
+   Like ``SETUP_FINALLY``, but in case of an exception also pushes the last
    instruction (``lasti``) to the stack so that ``RERAISE`` can restore it.
    If an exception occurs, the value stack level and the last instruction on
    the frame are restored to their current state, and control is transferred
@@ -1542,7 +1543,7 @@ but are replaced by real opcodes or removed before bytecode is generated.
 
 .. opcode:: SETUP_WITH (target)
 
-   Like ``SETUP_CLEANUP``, but in case of exception one more item is popped
+   Like ``SETUP_CLEANUP``, but in case of an exception one more item is popped
    from the stack before control is transferred to the exception handler at
    ``target``.
 
@@ -1576,7 +1577,7 @@ Opcode collections
 These collections are provided for automatic introspection of bytecode
 instructions:
 
-   .. versionchanged:: 3.12
+.. versionchanged:: 3.12
    The collections now contain pseudo instructions as well. These are
    opcodes with values ``>= MIN_PSEUDO_OPCODE``.
 
@@ -1609,10 +1610,10 @@ instructions:
 
 .. data:: hasfree
 
-   Sequence of bytecodes that access a free variable (note that 'free' in this
+   Sequence of bytecodes that access a free variable. 'free' in this
    context refers to names in the current scope that are referenced by inner
    scopes or names in outer scopes that are referenced from this scope.  It does
-   *not* include references to global or builtin scopes).
+   *not* include references to global or builtin scopes.
 
 
 .. data:: hasname