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+:mod:`token` --- Constants used with Python parse trees
+=======================================================
+
+.. module:: token
+ :synopsis: Constants representing terminal nodes of the parse tree.
+.. sectionauthor:: Fred L. Drake, Jr. <fdrake@acm.org>
+
+
+This module provides constants which represent the numeric values of leaf nodes
+of the parse tree (terminal tokens). Refer to the file :file:`Grammar/Grammar`
+in the Python distribution for the definitions of the names in the context of
+the language grammar. The specific numeric values which the names map to may
+change between Python versions.
+
+This module also provides one data object and some functions. The functions
+mirror definitions in the Python C header files.
+
+
+.. data:: tok_name
+
+ Dictionary mapping the numeric values of the constants defined in this module
+ back to name strings, allowing more human-readable representation of parse trees
+ to be generated.
+
+
+.. function:: ISTERMINAL(x)
+
+ Return true for terminal token values.
+
+
+.. function:: ISNONTERMINAL(x)
+
+ Return true for non-terminal token values.
+
+
+.. function:: ISEOF(x)
+
+ Return true if *x* is the marker indicating the end of input.
+
+
+.. seealso::
+
+ Module :mod:`parser`
+ The second example for the :mod:`parser` module shows how to use the
+ :mod:`symbol` module.
+