f = open(r'c:\text\somefile.txt', 'w') f.write('01234567890123456789') f.seek(5) f.write('Hello, World!') f.close() f = open(r'c:\text\somefile.txt') print f.read() f = open(r'c:\text\somefile.txt') print f.read(3) print f.read(2) print f.tell()