None placeholder : variable « Introduction « Python Tutorial






  1. Python Tutorial
  2. Introduction
  3. variable
X = None                                     # None placeholder
print X 
L = [None] * 100                             # Initialize a list of 100 Nones
print L 

print type(L)                                # Types
print type(type(L))                          # Even types are objects








1.5.variable
1.5.1.A variable is basically a name that represents some value
1.5.2.Sequence Unpacking
1.5.3.A literal is a number or string that appears directly in a program.
1.5.4.Python is dynamically typed, no pre-declaration of a variable or its type is necessary.
1.5.5.Once a variable has been assigned, you can access it by using its name
1.5.6.None placeholder