The head is empty and empty. Just practicing English will not have any effect. The best effect is to practice English thinking and systematic thinking. Yesterday's study a lot, let's review, have appetizers, use python interpreter, parameter passing, interactive mode, interpreter and its environment, source code encoding python, use python as counter, number, string, List, the first step of programming, in-depth Python flow control, if statements, for statements, range functions, break and continue statements, and else clauses in the loop, pass statements, define functions, deep into python function definitions, default parameter values, Keyword parameters, variable parameter lists, parameter list splits, lambda forms, document strings, function annotations.