Other tokens
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Besides NEWLINE, INDENT and DEDENT, the following categories of tokens
exist: _identifiers_, _keywords_, _literals_, _operators_, and
_delimiters_. Whitespace characters (other than line terminators,
discussed earlier) are not tokens, but serve to delimit tokens. Where
ambiguity exists, a token comprises the longest possible string that
forms a legal token, when read from left to right.