Variables, Expression and Assignment Statements
Variable naming rule and convention: Can not start with a digit Uppercase and lowercase letters Digits Underscore '_' By convention, variable names are lowercase, separated by _ Variable names are case sensitive List of identifiers and reserved keywords: https://docs.python.org/3/reference/lexical_analysis.html#identifiers Note above, since "area" was calculated before size change its value, area still 9 even though size is now 5 Syntax vs Semantic Errors: Above shows difference between syntax and semantic errors, though I really like this explanation. Expression vs Assignment Statement: Expression: evaluate, return/yield value/result Assignment: change state of variable/computaion and Python shell doesn't return anything Note: zipcode = '15245' zipcode + 3, Error because we can't add a type str and a type int zipcode * 3 will return 3 copies of zipcode, ie '152451524515245' z == (x * y...