how to remove the very last character of a text file in python

file.truncate(file.tell - 1)
#explanation - the function truncate will resize the file to the 
#full size - 1 and that means it will remove the last character
#if you need to do that while you are reading/writing somewhere using
#seek() you can use this function ->
def get_size(fileobject):
    fileobject.seek(0,2) # move the cursor to the end of the file
    size = fileobject.tell()
    return size
#and then
fsize = get_size(file)
file.truncate(fsize - 1)

Here is what the above code is Doing:
1. Open the file in read mode.
2. Read the file into a string.
3. Close the file.
4. Open the file in write mode.
5. Write the string to the file.
6. Close the file.