python代码题，对里面的知识点有困惑

Question

对字符串相关内容不熟悉，想知道里面的要求要用什么语句来满足，诚恳求学，希望能够解答

Answer 1

def count(s):
  alpha,num,space,other=0,0,0,0
  for i in s:
    if i.isalpha():
        alpha+=1
    elif i.isdigit():
        num+=1
    elif i.isspace():
        space+=1
    else:
        other+=1
  print('英文字符数{},数字字符数{},空格字符数{},其他字符数{}'.format(alpha,num,space,other))
  if alpha==len(s):
      return 1
  return 0
t=0
l=[]
for i in range(10):
    s=input("请输入一个字符串：")
    l.append(s)
    t+=count(s)
if t==10:
    for i in l:
        print(i.upper ())
else:
    print('不存在单纯字母字符串')