Python

raw_input and input

raw_input, return a string, has been removed and renamed as input in Python 3

input, return the result of the input expression, has been removed in Python 3, in which can be simulated by eval(input())

#!/usr/bin/python

# return a string
a = raw_input("Input an integer:\n");
print type(a), a;

# return the value of python expression
b = input ("Input an integer:\n");
print type(b), b;

Read

#!/usr/bin/python

# open file
f = open('Generator.htm', 'rb');

# read line by line
for index, line in enumerate(f):
    print index, line,

# back to starting position
f.seek(0, 0);

# display the current position
print f.tell();

# read line by line
try:
    while True:
        print f.next(), # raise StopIteration when hit EOF
except StopIteration:
    pass;

f.seek(0, 0)
# read character by character
while True:
    c = f.read(1);
    if not c:
        break;
    print "%10s, %10d" % (c, ord(c));

# close file
f.close();

Write

#!/usr/bin/python

# open file
f = open('Generator.htm', 'rb');
o = open('temp.htm', 'wb');

# read line by line
for index, line in enumerate(f):
    s = '{:10d} {}'.format(index, line);
    o.write(s);

f.close();
o.close();

Reference

Tutorialspoint.com