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How to replace two different lines of text?

I need to create a file that changes the date and name of a .txt, but I can only change one or the other with this code I found on the internet, can anyone give me any tips?
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import os
from ast import Str
file = open("example.txt", "r")
replacement = ""
data = "02/07/2022"
name = "Alan"
for line in file:
line = line.strip()
changes = line.replace("__/__/____", data)
replacement = replacement + changes + "\n"
file.close()
fout = open("final.txt", "w")
fout.write(replacement)
fout.close()

You don't need to do this a line a time. You can replace that entire program with this:
data = "02/07/2022"
name = "Alan"
text = open("example.txt", "r").read().replace("__/__/____", data)
open("final.txt", "w").write(text)

How to replace a line that has a specific text

I want to search for particular text and replace the line if the text is present in that line.
In this code I replace line 125, but want to replace dynamically according to the text:
file = open("config.ini", "r")
lines = file.readlines()
lines[125] = "minimum_value_gain = 0.01" + '\n'
f.writelines(lines)
f.close()
How do I make it that if a line has:
minimum_value_gain =
then replace that line with:
minimum_value_gain = 0.01

There is no reason for you to manually parse a config.ini file textually. You should use configparser to make things much simpler. This library reads the file for you, and in a way converts it to a dict so processing the data is much easier. For your task you can do something like:
import configparser
config = configparser.ConfigParser()
config.read("config.ini")
for section in config:
if config.has_option(section, "minimum_value_gain"):
config.set(section, "minimum_value_gain", "0.01")
with open("config.ini", 'w') as f:
config.write(f)

Since you are replacing complete line so if statement will do the trick for you, no need to replace text
#updated make sure one line doesn't have both values
file = open("config.ini", "r")
lines=file.readlines()
newlines = []
for line in lines:
if "minimum_value_gain" in line:
line = "minimum_value_gain = 0.01" + '\n'
if "score_threshold" in line:
line = "Values you want to add"+'\n'
newlines.append(line)
f.writelines(newlines)
f.close()

Little bit messy and not optimized but get's the job the, first readlines and inserts the next_text to the given pos(line). If the line doesn't exists Raises IndexError, else writes to the file
def replace_in_file(filename: str, search_text: str, string_to_add: str) -> None:
with open(filename, "r+") as file_to_write:
lines = file_to_write.readlines()
file_to_write.seek(0)
file_to_write.truncate()
for line in lines:
if line.startswith(search_text):
line = line.rstrip("\n") + string_to_add + "\n"
file_to_write.write(line)
replace_in_file("sdf.txt", "minimum_value_gain", " = 0.01")

You can use also the regex library of Python.
Here is an example.
It is better not to read and write in the same file, that is not good practice. Write in a different file then eventually rename it.
import re
pattern = 'minimum_value_gain'
string_to_replace = 'minimum_value_gain = 0.01\n'
file = open("config.ini", "r")
fileout = open("new_config.ini", "a")
lines=file.readlines()
newlines = [string_to_replace if re.match(pattern, line) else line for line in lines]
f.close()
fileout.writelines(lines)
fileout.close()
You can rename the file afterwards :
import os
os.remove("config.ini")
os.rename("new_config.ini", "config.ini")

Set the string you would like to look for (match_string = 'example')
Have a list output_list that is empty
Use with open(x,y) as z: (this will automatically close the file after completion)
for each line in file.readlines() - run through each line of the file
The if statement adds your replacement line if the match_string is in the line, else just the adds the line
NOTE: All variables can be any name that is not reserved (don't call something just 'list')
match_string = 'example'
output_list = []
with open("config.ini", "r") as file:
for line in file.readlines():
if match_string in line:
output_list.append('minimum_value_gain = 0.01\n')
else:
output_list.append(line)
Maybe not ideal for the first introduction to Python (or more readable) - But I would have done the problem as follows:
with open('config.ini', 'r') as in_file:
out_file = ['minimum_value_gain = 0.01\n' if 'example' in line else line for line in in_file.readlines()]

To replace a specific text in a string
a = 'My name is Zano'
b = a.replace('Zano', 'Zimmer')

Copy last line in python file and modify it before adding a new line

I would like to check for a string "rele" in a python text file and if string is not present then copy the last line of the file and then modify it as below to add as a new entry.
Example:
Actual File: Where "rele" is not present
"123456",1,0,"mher",0,"N",01Jan1986 00:00,130:00,
"123456",1,1,"ermt",0,"N",01Jan1986 00:00,100:00,
"123456",1,2,"irbt",0,"N",01Jan1986 00:00,120:00,
Expected Output:
"123456",1,0,"mher",0,"N",01Jan1986 00:00,130:00,
"123456",1,1,"ermt",0,"N",01Jan1986 00:00,0:00,
"123456",1,2,"irbt",0,"N",01Jan1986 00:00,0:00,
"123456",1,3,"rele",0,"0000",01Jan1986 00:00,0:00,
Last entry of the file is similar to its previous except few changes to it's 3,4 and 6 columns.
My code:
fp = open(srcEtab.txt, 'w')
for line in lines:
if 'rele' in line:
foundRelOrPickup = True
if not foundRelOrPickup:
fp1 = open ( 'srcEtab.txt',"w" )
lineList = fp1.readlines()
new_line = lineList[len(lineList)-1]
fp1.write(new_line)
fp.close()
fp1.close()

with open(yourFile) as f:
lines = f.readlines()
if not any(map(lambda line: "rele" in line,lines)):
last_line_words = lines[-1].split(',')
last_line_words[2] = len(lines)
last_line_words[3] = '"rele"'
last_line_words[5] = '"0000"'
lines.append(",".join([str(i) for i in last_line_words]))
with open(otherFile, "w") as f1:
for line in lines:
f1.write(line)

Python : Why do new lines keep appearing after every value amend?

I'm new to python and I'm trying various small things to see how they work:
items = dict()
with open(path) as f:
content = f.readlines()
for line in content:
splitStuff = line.split('!')
if splitStuff[0] in item:
items[splitStuff[0]] += ',' + Results[1]
else:
items[splitStuff[0]] = Results[1]
f.close()
with open(path2, 'a') as f:
for key, value in items.items():
f.write(key + '!' + value)
f.close()
It opens a file with this content:
3!Angel
3!Devil
4!Nasko
4!Pesho
4!Gosho
5!Kalin
6!Gancho
6!Boncho
6!Toncho
6!Moncho
And ends up writing a file with this content:
3!Angel
,Devil
4!Nasko
,Pesho
,Gosho
5!Kalin
6!Gancho
,Boncho
,Toncho
,Moncho
The part I don't understand is where are those new lines appearing from every time I edit a value?
EDIT: This is the desired output.
3!Angel,Devil
4!Nasko,Pesho,Gosho
5!Kalin
6!Gancho,Boncho,Toncho,Moncho
EDIT2: Never mind figured it out. Its because there are new lines in the original file and apparently reading file line by line catches them as well in python, unlike c# where they are ignored.

Lines you read with readlines() have a trailing newline.
for line in content:
line = line.rstrip()
splitStuff = line.split('!')
... etc ...

A solution could look like this:
path = "file1"
path2 = "file2"
items = dict()
with open(path) as f:
content = f.readlines()
for line in content:
splitStuff = line.split('!')
if splitStuff[0] in items:
items[splitStuff[0]] += ',' + splitStuff[1][:-1]
else:
items[splitStuff[0]] = splitStuff[1][:-1]
f.close()
with open(path2, 'a') as f:
for key, value in items.items():
f.write(key + '!' + value)
f.write("\n")
f.close()
You just had to remove the newline from each line of the file by adding [:-1].

Using python to read txt files and answer questions

a01:01-24-2011:s1
a03:01-24-2011:s2
a02:01-24-2011:s2
a03:02-02-2011:s2
a03:03-02-2011:s1
a02:04-19-2011:s2
a01:05-14-2011:s2
a02:06-11-2011:s2
a03:07-12-2011:s1
a01:08-19-2011:s1
a03:09-19-2011:s1
a03:10-19-2011:s2
a03:11-19-2011:s1
a03:12-19-2011:s2
So I have this list of data as a txt file, where animal name : date : location
So I have to read this txt file to answer questions.
So so far I have
text_file=open("animal data.txt", "r") #open the text file and reads it.
I know how to read one line, but here since there are multiple lines im not sure how i can read every line in the txt.

Use a for loop.
text_file = open("animal data.txt","r")
for line in text_file:
line = line.split(":")
#Code for what you want to do with each element in the line
text_file.close()

Since you know the format of this file, you can shorten it even more over the other answers:
with open('animal data.txt', 'r') as f:
for line in f:
animal_name, date, location = line.strip().split(':')
# You now have three variables (animal_name, date, and location)
# This loop will happen once for each line of the file
# For example, the first time through will have data like:
# animal_name == 'a01'
# date == '01-24-2011'
# location == 's1'
Or, if you want to keep a database of the information you get from the file to answer your questions, you can do something like this:
animal_names, dates, locations = [], [], []
with open('animal data.txt', 'r') as f:
for line in f:
animal_name, date, location = line.strip().split(':')
animal_names.append(animal_name)
dates.append(date)
locations.append(location)
# Here, you have access to the three lists of data from the file
# For example:
# animal_names[0] == 'a01'
# dates[0] == '01-24-2011'
# locations[0] == 's1'

You can use a with statement to open the file, in case of the open was failed.
>>> with open('data.txt', 'r') as f_in:
>>> for line in f_in:
>>> line = line.strip() # remove all whitespaces at start and end
>>> field = line.split(':')
>>> # field[0] = animal name
>>> # field[1] = date
>>> # field[2] = location

You are missing the closing the file. You better use the with statement to ensure the file gets closed.
with open("animal data.txt","r") as file:
for line in file:
line = line.split(":")
# Code for what you want to do with each element in the line