aa="岳麓区人民欢迎您"
print(aa)
print(aa[0])
print(aa[-1])
username='xiaoming'
print(username)
print(username.upper())
unsername1=username.upper()
print(unsername1)
print(unsername1.lower())
print(len(username))
str="Hello_world"
print(str.upper())
print(str[2:8])
print(len(str))
print(str[-2])
print(str.split('_'))
mylist=[10,20,30,40,50]
print(mylist)
print(mylist[1])