How to avoid duplication when replacing by using two lists

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I'm working on replacing words using two lists

a = ["Strawberry Cookie", "Banana Cookie", "Tomato Cookies", "Pineapple Cookie", "Apple Cookie"]

b = ["Pineapple Cookie", "Cookie Banana", "Cookie Tomato", "Strawberry Cookie", "Cookie Apple"]

Retrieves the string in variable text1 into a list (a) and replaces it with a list (b). The sequence of tasks is in the same order as the list.

text1 = """

Meaningless texts are listed aaaa

aaaaaaaaa Strawberry Cookie aaaaaaa

ccccc Meaningless texts are listed aaaaa

aaaaaaaaa Banana Cookie aaaaaa
bbbb Meaningless texts are listed aaaa

aaaaaaaa Tomato Cookies aaaaaaaa

aaaa Meaningless texts are listed aaaa
aaaaaaaa Pineapple Cookie aaaaaaa

aaaaaa Apple Cookie aaaaaaa
gggsdgg Meaningless texts are listed affff

dsddsssf

"""

I tried the code below.

for x, y in zip(a, b):
    text1 = re.sub(x, y, text1, re.IGNORECASE)
print text1

>>>Meaningless texts are listed aaaa

aaaaaaaaa Strawberry Cookie aaaaaaa

ccccc Meaningless texts are listed aaaaa

aaaaaaaaa Cookie Banana aaaaaa
bbbb Meaningless texts are listed aaaa

aaaaaaaa Cookie Tomato aaaaaaaa

aaaa Meaningless texts are listed aaaa
aaaaaaaa Strawberry Cookie aaaaaaa

aaaaaa Cookie Apple aaaaaaa
gggsdgg Meaningless texts are listed affff

dsddsssf

Due to the duplicate values of Strawberry Cookie and Pineapple Cookie in the list (a) and (b), the replacement operation is made twice and it returns to the original value.

What I want is to set the value to not change once it is substituted.

new_text = []
check_list = []
num = 0
division = text.split('\n')

for line in division:
    for i in range(len(b)):
        if a[i] in line:
            if a[i] not in check_list:
                check_list.append(b[i])
                rrr = re.sub(a[i], b[i], line, re.IGNORECASE)
                new_text.append(rrr)
                break
            else:
                check_list.append(b[i])
                new_text.append(line)

        else:
            check_list.append(b[i])
            new_text.append(line)
            break

I've tried several times, but failed. Help

python replace
1 Answers

Here is one trick you may use. You can construct a regex alternation of all the search terms in list a. Then use re.sub with a callback function, and in the callback access the replacement directly from the dictionary of replacements which you have already built. This avoids the problem of double substitution, because the text is only scanned once, from start to finish.

a = ["Strawberry Cookie", "Banana Cookie", "Tomato Cookies", "Pineapple Cookie", "Apple Cookie"]
b = ["Pineapple Cookie", "Cookie Banana", "Cookie Tomato", "Strawberry Cookie", "Cookie Apple"]
d = dict(zip(a, b))
regex = r'\b(?:' + r'|'.join(a) + r')\b'
output = re.sub(regex, lambda m: d[m.group()], text1)
print(output)

This prints:

Meaningless texts are listed aaaa

aaaaaaaaa Pineapple Cookie aaaaaaa

ccccc Meaningless texts are listed aaaaa

aaaaaaaaa Cookie Banana aaaaaa
bbbb Meaningless texts are listed aaaa

aaaaaaaa Cookie Tomato aaaaaaaa

aaaa Meaningless texts are listed aaaa
aaaaaaaa Strawberry Cookie aaaaaaa

aaaaaa Cookie Apple aaaaaaa
gggsdgg Meaningless texts are listed affff

dsddsssf
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