One method needs to be defined for container objects to provide iteration
support:
+.. XXX duplicated in reference/datamodel!
-.. method:: object.__iter__()
+.. method:: container.__iter__()
Return an iterator object. The object is required to support the iterator
protocol described below. If a container supports different types of
Debug-mode variables
---------------------
+~~~~~~~~~~~~~~~~~~~~
Setting these variables only has an effect in a debug build of Python, that is,
-if Python was configured with the :opt:`--with-pydebug` build option.
+if Python was configured with the :option:`--with-pydebug` build option.
.. envvar:: PYTHONTHREADDEBUG