>>> import sys
>>> print sys.__doc__

This module provides access to some objects used or maintained by the
interpreter and to functions that interact strongly with the interpreter.

$ Python --version
Python 2.7.6

$ Python --help
usage: Python [option] ... [-c cmd | -m mod | file | -] [arg] ...
Options and arguments (and corresponding environment variables):
-B : don't write .py[co] files on import; also PYTHONDONTWRITEBYTECODE=x
-c cmd : program passed in as string (terminates option list)
-d : debug output from parser; also PYTHONDEBUG=x
-E : ignore PYTHON* environment variables (such as PYTHONPATH)
-h : print this help message and exit (also --help)
-i : inspect interactively after running script; forces a prompt even
    if stdin does not appear to be a terminal; also PYTHONINSPECT=x
-m mod : run library module as a script (terminates option list)
-O : optimize generated bytecode slightly; also PYTHONOPTIMIZE=x
-OO : remove doc-strings in addition to the -O optimizations
-R : use a pseudo-random salt to make hash() values of various types be
    unpredictable between separate invocations of the interpreter, as
    a defense against denial-of-service attacks

#!/usr/bin/env Python
# coding=utf-8
import sys
print "The file name: ", sys.argv[0]
print "The number of argument", len(sys.argv)
print "The argument is: ", str(sys.argv)

$ python 22101.py
The file name: 22101.py
The number of argument 1
The argument is: ['22101.py']

$ python 22101.py beginner master www.itdiffer.com
The file name: 22101.py
The number of argument 4
The argument is: ['22101.py', 'beginner', 'master', 'www.itdiffer.com']

Help on built-in function exit in module sys:
exit(...)
    exit([status])
    Exit the interpreter by raising SystemExit(status).
    If the status is omitted or None, it defaults to zero (i.e., success).
    If the status is an integer, it will be used as the system exit status.
    If it is another kind of object, it will be printed and the system
    exit status will be one (i.e., failure)

#!/usr/bin/env Python
# coding=utf-8
import sys
for i in range(10):
    if i == 5:
        sys.exit()
    else:
        print i

$ python 22102.py
0
1
2
3
4

>>> for i in range(3):
... print i
...
0
1
2
>>> import sys
>>> for i in range(3):
... sys.stdout.write(str(i))
...
012>>>

>>> for i in range(3):
... sys.stdout.write(str(i) + '\n')
...
0
1
2

>>> f = open("stdout.md", "w")
>>> sys.stdout = f
>>> print "Learn Python: From Beginner to Master"
>>> f.close()

$ cat stdout.md
Learn Python: From Beginner to Master

>>> import copy
>>> copy.__all__
['Error', 'copy', 'deepcopy']

#!/usr/bin/env Python
# coding=utf-8
import copy
class MyCopy(object):
    def __init__(self, value):
        self.value = value
    def __repr__(self):
        return str(self.value)
foo = MyCopy(7)
a = ["foo", foo]
b = a[:]
c = list(a)
d = copy.copy(a)
e = copy.deepcopy(a)
a.append("abc")
foo.value = 17
print "original: %r\n slice: %r\n list(): %r\n copy(): %r\n deepcopy(): %r\n" % (a,b,c,d,e)

$ python 22103.py
original: ['foo', 17, 'abc']
slice: ['foo', 17]
list(): ['foo', 17]
copy(): ['foo', 17]
deepcopy(): ['foo', 7]