After discussing some more with Georg, do no migrate versionchanged:: 2.5 to

this branch. While I am here, also get rid of other versionchanged:: 2.x
constructs, as discussed.

Doc/c-api/sequence.rst

@@ -21,10 +21,6 @@ Sequence Protocol
    For objects that do not provide sequence protocol, this is equivalent to the
    Python expression ``len(o)``.
 
-   .. versionchanged:: 2.5
-      These functions returned an :ctype:`int` type. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: PyObject* PySequence_Concat(PyObject *o1, PyObject *o2)
 
@@ -37,10 +33,6 @@ Sequence Protocol
    Return the result of repeating sequence object *o* *count* times, or *NULL* on
    failure.  This is the equivalent of the Python expression ``o * count``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *count*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: PyObject* PySequence_InPlaceConcat(PyObject *o1, PyObject *o2)
 
@@ -55,30 +47,18 @@ Sequence Protocol
    failure.  The operation is done *in-place* when *o* supports it.  This is the
    equivalent of the Python expression ``o *= count``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *count*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: PyObject* PySequence_GetItem(PyObject *o, Py_ssize_t i)
 
    Return the *i*th element of *o*, or *NULL* on failure. This is the equivalent of
    the Python expression ``o[i]``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: PyObject* PySequence_GetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2)
 
    Return the slice of sequence object *o* between *i1* and *i2*, or *NULL* on
    failure. This is the equivalent of the Python expression ``o[i1:i2]``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i1* and *i2*. This might
-      require changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: int PySequence_SetItem(PyObject *o, Py_ssize_t i, PyObject *v)
 
@@ -86,40 +66,24 @@ Sequence Protocol
    is the equivalent of the Python statement ``o[i] = v``.  This function *does
    not* steal a reference to *v*.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: int PySequence_DelItem(PyObject *o, Py_ssize_t i)
 
    Delete the *i*th element of object *o*.  Returns ``-1`` on failure.  This is the
    equivalent of the Python statement ``del o[i]``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: int PySequence_SetSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2, PyObject *v)
 
    Assign the sequence object *v* to the slice in sequence object *o* from *i1* to
    *i2*.  This is the equivalent of the Python statement ``o[i1:i2] = v``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i1* and *i2*. This might
-      require changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: int PySequence_DelSlice(PyObject *o, Py_ssize_t i1, Py_ssize_t i2)
 
    Delete the slice in sequence object *o* from *i1* to *i2*.  Returns ``-1`` on
    failure.  This is the equivalent of the Python statement ``del o[i1:i2]``.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i1* and *i2*. This might
-      require changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: Py_ssize_t PySequence_Count(PyObject *o, PyObject *value)
 
@@ -127,10 +91,6 @@ Sequence Protocol
    of keys for which ``o[key] == value``.  On failure, return ``-1``.  This is
    equivalent to the Python expression ``o.count(value)``.
 
-   .. versionchanged:: 2.5
-      This function returned an :ctype:`int` type. This might require changes
-      in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: int PySequence_Contains(PyObject *o, PyObject *value)
 
@@ -144,10 +104,6 @@ Sequence Protocol
    Return the first index *i* for which ``o[i] == value``.  On error, return
    ``-1``.    This is equivalent to the Python expression ``o.index(value)``.
 
-   .. versionchanged:: 2.5
-      This function returned an :ctype:`int` type. This might require changes
-      in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: PyObject* PySequence_List(PyObject *o)
 
@@ -178,10 +134,6 @@ Sequence Protocol
    Return the *i*th element of *o*, assuming that *o* was returned by
    :cfunc:`PySequence_Fast`, *o* is not *NULL*, and that *i* is within bounds.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: PyObject** PySequence_Fast_ITEMS(PyObject *o)
 
@@ -200,10 +152,6 @@ Sequence Protocol
    :cfunc:`PySequence_Check(o)` is true and without adjustment for negative
    indices.
 
-   .. versionchanged:: 2.5
-      This function used an :ctype:`int` type for *i*. This might require
-      changes in your code for properly supporting 64-bit systems.
-
 
 .. cfunction:: Py_ssize_t PySequence_Fast_GET_SIZE(PyObject *o)