This module provides constants which represent the numeric values ofinternal nodes of the parse tree. Unlike most Python constants, theseuse lower-case names. Refer to the file \file{Grammar/Grammar} in thePython distribution for the defintions of the names in the context ofthe language grammar. The specific numeric values which the names mapto may change between Python versions.This module also provides one additional data object:\begin{datadesc}{sym_name}Dictionary mapping the numeric values of the constants defined in thismodule back to name strings, allowing more human-readablerepresentation of parse trees to be generated.\end{datadesc}\begin{seealso}\seemodule{parser}{second example uses this module}\end{seealso}