How to add a value to a specific line in a file in python?

Question

I've seen really complex answers on this website as how to edit a specific line on a file but I was wondering if there was a simple way to do it? I want to search for a name in a file, and on the line that I find that name on, I want to add an integer to the end of the line (as it is a score for a quiz). Or could you tell me how I can replace the entirety of the line with new data? I have tried a lot of coding but either no change is made, or all of the data in the file gets deleted. I tried this....

with open ('File.py', 'r') as class_file:
        for number, line in enumerate(class_file):
            if name in line:
                s=open('File.py', 'r').readlines()
                s[number]=str(data)
                class_file=open('File.py', 'w')
                class_file.writelines(new_score)
                class_file.close()

As well as this function....

def replace (file, line_number, add_score):
    s=open(file, 'w')
    new_data=line[line_number].replace(line, add_score)
    s.write(str(new_data))
    s.close()

As well as this...

def replace_score(file_name, line_num, text):
    new = open(file_name, 'r').readlines()
    new[line_num] = text
    adding_score= open(file_name, 'w')
    adding_score.writelines(new)
    adding_score.close()

But I still can't get it to work. The last code works if I'm trying to replace the first line, but not the others.

Answer 1

You need to get the content of the file. Close the file. Modify the content and rewrite the file with the modified content. Try the following:

def replace_score(file_name, line_num, text):
  f = open(file_name, 'r')
  contents = f.readlines()
  f.close()

  contents[line_num] = text+"\n"

  f = open(file_name, "w")
  contents = "".join(contents)
  f.write(contents)
  f.close()

replace_score("file_path", 10, "replacing_text")

Answer 2

This is Tim Osadchiy's code:

def replace_score(file_name, line_num, text):
     f = open(file_name, 'r')
     contents = f.readlines()
     f.close()

     contents[line_num] = text+"\n"

     f = open(file_name, "w")
     contents = "".join(contents)
     f.write(contents)
     f.close()

replace_score("file_path", 10, "replacing_text")

This code does work but just remember that the line_num will always be one above the actual line number (as it is an index). So if you wanted line 9 then enter 8, not 9. Also, do not forget to put .txt at the end of the file path (I would've commented but do not have a high enough reputation)