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How to find and replace multiple lines in a text file?

I am running Python 2.7.

I have three text file: data.txt, find.txtand replace.txt. Now it find.txtcontains several lines that I want to find in data.txt, and replace this section with the contents in replace.txt. Here is a simple example:

data.txt

pumpkin
apple
banana
cherry
himalaya
skeleton
apple
banana
cherry
watermelon
fruit

find.txt

apple
banana
cherry

replace.txt

1
2
3

So, in the above example, I want to find all occurrences apple, bananaand cherryin the data, and replace these lines with 1,2,3.

, data.txt 1 , . - replace, , .

import re

data = open("data.txt", 'r')
find = open("find.txt", 'r')
replace = open("replace.txt", 'r')

data_str = ""
find_str = ""
replace_str = "" 

for line in data: # concatenate it into one long string
    data_str += line

for line in find: # concatenate it into one long string
    find_str += line

for line in replace: 
    replace_str += line


new_data = data_str.replace(find, replace)
new_file = open("new_data.txt", "w")
new_file.write(new_data)

, . , replace , .

, .

- :

location = 0

LOOP1: 
for find_line in find:
    for i, data_line in enumerate(data).startingAtLine(location):
        if find_line == data_line:
            location = i # found possibility

for idx in range(NUMBER_LINES_IN_FIND):
    if find_line[idx] != data_line[idx+location]  # compare line by line
        #if the subsequent lines don't match, then go back and search again
        goto LOOP1

, . , , , . ?

!

+3
2

, read write , .

# create a dict of find keys and replace values
findlines = open('find.txt').read().split('\n')
replacelines = open('replace.txt').read().split('\n')
find_replace = dict(zip(findlines, replacelines))

with open('data.txt') as data:
    with open('new_data.txt', 'w') as new_data:
        for line in data:
            for key in find_replace:
                if key in line:
                    line = line.replace(key, find_replace[key])
            new_data.write(line)

: read().split('\n') readliens(), \n

+3

:

replace , . : Python 2.7:

, data.txt , data.txt

data = open("data.txt", 'r')
for line in data:
    # fix the line

, , / . zip

find = open("find.txt", 'r').readlines()
replace = open("replace.txt", 'r').readlines()
new_data = open("new_data.txt", 'w')
for find_token, replace_token in zip(find, replace):
    new_line = line.replace(find_token, replace_token)
    new_data.write(new_line + os.linesep)
+1

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