使用pycharm编写python程序的时候，总会在def function()有以下问题：
PEP 8: E302 expected 2 blank lines, found 1造成这个问题的原因：在声明函数的行上方必须有两行空行，否则就会发生这种情况。
eg:
# This is a sample Python script. # Press Shift F10 to execute it or replace it with your code. # Press Double Shift to search everywhere for classes, files, tool windows, actions, and settings. def print_hi(name): # Use a breakpoint in the code line below to debug your script. print(f'Hi, {name}') # Press Ctrl F8 to toggle the breakpoint. def print_string(): # 字符串声明：单引号和双引号等价 name1 = 'Hi Python3' print(name1) name2 = "Hi Python3" print(name2) # 字符串声明：三引号包含多行字符串 name3 = """Hi Python3""" print(name3) # Press the green button in the gutter to run the script. if __name__ == '__main__': print_hi('PyCharm') # 整数相加 print(2 2) # 浮点数相加 print(2.0 2.5) # 整数加浮点数 print(2 2.5) # 变量赋值 a = 10 print(a) # 字符串声明函数 print_string() # See PyCharm help at https://www.jetbrains.com/help/pycharm/