Pending removal in Python 3.21
******************************

* "abc"

     * Soft-deprecated since Python 3.3 "abc.abstractclassmethod",
       "abc.abstractstaticmethod", and "abc.abstractproperty" now
       raise a "DeprecationWarning". These classes will be removed in
       Python 3.21, instead use "abc.abstractmethod()" with
       "classmethod()", "staticmethod()", and "property" respectively.

* "ast":

  * Classes "slice", "Index", "ExtSlice", "Suite", "Param", "AugLoad"
    and "AugStore", will be removed in Python 3.21. These types are
    not generated by the parser or accepted by the code generator.

  * The "dims" property of "ast.Tuple" will be removed in Python 3.21.
    Use the "ast.Tuple.elts" property instead.
