在Python中，为某些字母可以是数字的字符串生成所有可能

def generate_strings(string):
    result = []
    if len(string) == 0:
        return ['']
    elif len(string) == 1:
        if string.isdigit():
            return [string]
        else:
            return [string.lower(), string.upper()]
    else:
        first_char = string[0]
        remaining_string = string[1:]
        if first_char.isdigit():
            for sub_string in generate_strings(remaining_string):
                result.append(first_char + sub_string)
        else:
            for sub_string in generate_strings(remaining_string):
                result.append(first_char.lower() + sub_string)
                result.append(first_char.upper() + sub_string)
    return result

input_string = "a1B2"
output = generate_strings(input_string)
print(output)

['a1b2', 'a1B2', 'A1b2', 'A1B2']

def generate_strings(string):
    result = ['']
    for char in string:
        if char.isdigit():
            result = [prefix + char for prefix in result]
        else:
            result = [prefix + char.lower() for prefix in result] + [prefix + char.upper() for prefix in result]
    return result

input_string = "a1B2"
output = generate_strings(input_string)
print(output)

['a1b2', 'a1B2', 'A1b2', 'A1B2']