Python3 type in a string

S is a string

S.isalnum ()#all characters are numbers or letters, return Ture for true, or False. S.isalpha ()#all characters are letters and return Ture for true, otherwise False is returned. s.isdigit ()#all characters are numbers (integers), return Ture for true, or False. S.islower ()#all characters are lowercase and return Ture for true, otherwise False is returned. S.isupper ()#all characters are uppercase and return Ture for true, otherwise False is returned. S.istitle ()#all words are capitalized, return Ture true, or False. s.isspace ()#all characters are whitespace characters, return Ture for true, or False.          

If you want to determine if it is a floating-point number, you can catch it with an exception (this seems simpler), and the other is to use regular expressions:

str = input ("please input the number:"try:     =   Except  valueerror:     print(" input is not a number!") ")

Python3 type in a string