Update page 'Day 2 lecture'

Day 2 lecture.md

@@ -1,8 +1,18 @@
 * Review of day 1, questions
+bignums
+np.finfo(format) for format in ['float16','float32']
+mojibake
+
 * Lexer/parser demo
-* `tokenize` module
-* `ast` module
+finite state automaton or FSA, or "state machine"
+timers
+* `tokenize` module: https://docs.python.org/3/library/tokenize.html
+tokens can be used to debug complex data input issues, especially security or xplatform issues
+* `ast` module: https://docs.python.org/3/library/ast.html
+abstract syntax tree
 * Number formats, base 16 representation
+* Hexdumping: https://gogs.gtsplab.com:5432/j/python-test/src/main/hexdump.py
+ASCII tables
 * Imaginary numbers and why 'j' is a problem
+also i
 * Formatted string literals
-* Hexdumping