timing the improvements implementing sets built-in options set functions set classes optimizationmoving sets to dictionaries adding relational algebra to sets (externalsubclassing built-in types binary search trees built-in options implementing binary trees trees with both keys and values graph searching implementing graph search moving graphs to classes permuting sequences reversing and sorting sequences implementing reversals implementing sorts data structures versus built-insthe conclusion pytreea generic tree object viewer text and language "see jack hack hackjackhackstrategies for processing text in python string method utilities templating with replacements and formats parsing with splits and joins summing columns in file parsing and unparsing rule strings regular expression pattern matching the re module first examples string operations versus patterns using the re module more pattern examples scanning header files for patterns xml and html parsing xml parsing in action html parsing in action advanced language tools custom language parsers table of contents xix