def func(p):
digit_number= 0
alpha_number= 0
else_number= 0
for i in p:
if i.isdigit():
digit_number+= 1
elif i.isalpha():
alpha_number+= 1
else:
else_number+= 1
return(digit_number,alpha_number,else_number)
这段代码实现的是啥功能？求大佬讲解