可以使用Python的isalpha()和isdigit()方法来统计字符串中数字和字母的个数。下面是一个示例代码：
def count_alpha_digit(s):
alpha_count = 0
digit_count = 0
for char in s:
if char.isalpha():
alpha_count += 1
elif char.isdigit():
digit_count += 1
return alpha_count, digit_count
s = "Hello123"
alpha_count, digit_count = count_alpha_digit(s)
print(f"字母个数：{alpha_count}")
print(f"数字个数：{digit_count}")
运行以上代码将输出：
字母个数：5
数字个数：3
