我必须编写代码以识别模式并替换模式吗？

如何解决我必须编写代码以识别模式并替换模式吗？

我有一条问题语句，其中有一列模式，如果前四个字节有日期，则应将这四个字节替换为ccyy，其余部分替换为N，零替换为Z 例如。 20190045689-> CCYYZZNNNNN 如果是空间，我们还需要考虑空间。 66-7830956-> NN-NNNZNNN

def patternGeneration(string):
    x = re.findall("[\s0-9a-zA-Z]",string)
    n = len(x)
    j = 0
    r = re.compile("\A[^(19|20)]")
    y = list(filter(r.match,x))
    b = len(y)
    for i in range(0,b):
        if y[i] == "0":
            y[i] = 0
        elif y[i] == " ":
            y[i] = " "
        else:
            y[i] = "n"
    print(convert(y))

    for i in range(0,n):
        if x[i] == "0":
            x[i] = 0
            j = j + 1
        elif x[i] == " ":
            x[i] = " "
            j = j + 1
        else:
            x[i] = "n"
    print(convert(x))


str1 = input("enter the string\t")
patternGeneration(str1)

解决方法

#convert to new format
def convert(string):
    # check for year
    head = string[:4]
    tail = string[4:]
    if head.isnumeric():
        if 1900 <= int(head) <= 2099:
            head = "CCYY"
    new_string = head + tail

    return "".join(["Z" if x == "0" else "N" if x.isnumeric() else x for x in str(new_string)])

sample = "20196705540"
print(convert(sample))
#"CCYYNNZNNNZ"

sample = "66-7830956"
print(convert(sample))
#"NN-NNNZNNN"