The following code does the replacement in the given text file.
After the replacement, the text is written to a new text file 'bar.txt'
Example
f1 = open('foo.txt', 'r')
f2 = open('bar.txt', 'w')
for line in f1:
print line
f2.write(line.replace('Poetry', 'Prose'))
f2 = open('bar.txt', 'r')
for line in f2:
print line,
f1.close()
f2.close()Output
This gives the output
Poetry is often considered the oldest form of literature. Poetry today is usually written down, but is still sometimes performed. Prose is often considered the oldest form of literature. Prose today is usually written down, but is still sometimes performed.