The macros in this section are used for managing reference counts of Python objects.
Warning: The deallocation function can cause arbitrary Python code to be invoked (e.g. when a class instance with a __del__() method is deallocated). While exceptions in such code are not propagated, the executed code has free access to all Python global variables. This means that any object that is reachable from a global variable should be in a consistent state before Py_DECREF() is invoked. For example, code to delete an object from a list should copy a reference to the deleted object in a temporary variable, update the list data structure, and then call Py_DECREF() for the temporary variable.
The following functions or macros are only for internal use: _Py_Dealloc(), _Py_ForgetReference(), _Py_NewReference(), as well as the global variable _Py_RefTotal.
XXX Should mention Py_Malloc(), Py_Realloc(), Py_Free(), PyMem_Malloc(), PyMem_Realloc(), PyMem_Free(), PyMem_NEW(), PyMem_RESIZE(), PyMem_DEL(), PyMem_XDEL().