Imports in Python

What's the difference between: 1) import numpy, 2) import numpy as np, and 3) from numpy import * ?

First example:

import numpy

Second example:

import numpy as np

Third example:

from numpy import *

The first example allows usage of all sub-modules and functions in the numpy module- but they can only be accessed by numpy.method().

The second example is the same as the first example- but also sets up np as alias thru which to access the numpy functions- example: np.method().

The third example imports all sub-modules and functions from the numpy module into the local namespace. This allows using numpy's methods without namespace qualifications- example: method(). However, this has the disadvantage of complicating the local namespace with common method names- and overriding methods with the same names from other modules.