AST functions

The following functions are used to create the AST:

is_numeric(text)	Return True when a string is numeric.
multireplace(string, replacements[, ignore_case])	Given a string and a replacement map, return the replaced string.
split_trail_alpha(text)	Split a string based on the last tailing non-alphanumeric character.
to_py_name(name[, cmd_map])	Convert to a Python-compatible name.