How to split a large .txt file into many smaller .txt files using a specific line as a splitting point? - python-3.10

Question

I have a large .txt file containing location names/coordinates/other info. The format of the .txt file is as such.
LOCATION: ______
(all the data for that location
listed on multiple lines)
"______________________________________________________________________"
LOCATION: ______
(all the data for that location
listed on multiple lines)
"______________________________________________________________________"
etc.
Each set of smaller data within the larger .txt file is separated by a string of 70 underscores
I would like to be able to split the large .txt file into many smaller .txt files containing just one Location and all its specific data (all the lines between "LOCATION" and the 70 underscore string.
I would have used a line counter to do this but each smaller dataset contains a differing number of total lines.
Here is the code I've been working on to try and solve this.
import tempfile
import re
print("Enter the Name of File: ")
fileName = input() ### gets name of .txt file
fileHandle = open(fileName, "r")
largeData = fileHandle.read().splitlines()
NewfileName = fileName.replace('.txt', '_') ### creates a new file name without the .txt at the end)
i=0 ### counter for new smaller .txt names
tempData = tempfile.TemporaryFile(mode='w+t')
for line in largeData: ### goes though each line in largeData
tempData.writelines(line) ### adds each new line to tempData
if "LOCATION" in line: ### if the word "LOCATION" is found -> indicates a new set of data
Newfile = open(NewfileName + str(i) +".txt", 'w') ### creates a new file using the original file name plus the counter and replaces .txt at the end
for sLine in tempData: ### for every line currently in the tempData temporary file
Newfile.writelines(sLines) ### writes all lines from tempData to the Newly created file
i+=1 ### updates counter for next file name
Right now when I run the code and give it the large .txt file name I end up with the correct number and names for all the smaller .txt files but they are all empty. How do I get the files to contain each individual smaller dataset? Thank you!