Python First Commands to run on Interpreter, for first time Users

#FirstPythonCommands:

The first point I need to tell, the Python is a dynamic , interpreted language. The next best point is there are no type declarations for:

• Variables
• Methods
• Parameters
• Functions

More: Python String Comparison and Key points

Why Python code is so short? 

The main reason is no compile is required. During run time it validates the code and show errors if any.

How to test your code in Python
Just go into interpreter, and enter the following commands. So that you can see results.

$ python        ## Run the Python interpreter
Python 2.7.9 (default, Dec 30 2014, 03:41:42) [GCC 4.1.2 20080704 (Red Hat 4.1.2-55)] on linux2Type "help", "copyright", "credits" or "license" for more information.
>>> a = 6       ## set a variable in this interpreter session
>>> a           ## entering an expression prints its value
6
>>> a + 2
8
>>> a = 'hi'    ## 'a' can hold a string just as well
>>> a'hi'
>>> len(a)      ## call the len() function on a string
2
>>> a + len(a)  ## try something that doesn't work
Traceback (most recent call last):
  File "", line 1, in 
TypeError: cannot concatenate 'str' and 'int' objects>>> a + str(len(a))  ## probably what you really wanted
'hi2'
>>> foo         ## try something else that doesn't work
Traceback (most recent call last):
  File "", line 1, in 
NameError: name 'foo' is not defined
>>> ^D          ## type CTRL-d to exit (CTRL-z in Windows/DOS terminal)