1\string are immutable, which means you can‘t change an existing string.
>>>greeting = ‘Hello world!‘
>>>greeting[0] = ‘J‘
TypeError: object does not support item assignment
2\The world in is a boolean operator that takes two strings and returns True if the first appears as a substring in the second. For example, the following function prints all the letters from word1 that also appear in word2:
>>>def in_both(word1, word2):
>>> for letter in word1:
>>> if letter in word2:
>>> print letter
3\The relational operators work on strings.
All the uppercase letters come before all the lowercase letters
python学习--string,布布扣,bubuko.com
原文:http://www.cnblogs.com/siriuswang/p/3904916.html