摘要： Strings are amongst the most popular types（最常用的类型） in Python. We can create them simply by enclosing characters in quotes（引号引起来）. Python treats single 阅读全文

摘要： Operators（运算符） are the constructs which can manipulate the value of operands. Consider the expression 4 + 5 = 9. Here, 4 and 5 are called operands and 阅读全文