Copy a file line by line, OR add some processing before writing the line.
def copyLineByLine(fname):
with open(fname, 'r') as f_in, open('Copy.txt', 'w')as f_out:
for line in f_in:
# process the line here, if required
f_out.write(line)
print('done')
def writelinesf(fname):
# reads all lines in a file,
# then adds a second copy to the end of the file.
#
f = open(fname, 'r+')
lines = f.readlines()
f.writelines(lines)
f.close()