A module is a file containing Python definitions and statements. A module can define functions, classes, and variables. A module can also include runnable code. Grouping related code into a module makes the code easier to understand and use. It also makes the code logically organized.
Example:
Python
# A simple module, calc.py def add(x, y): return (x + y) def subtract(x, y): return (x - y) |
The import statement
We can use any Python source file as a module by executing an import statement in some other Python source file.
When the interpreter encounters an import statement, it imports the module if the module is present in the search path. A search path is a list of directories that the interpreter searches for importing a module. For example, to import the module calc.py, we need to put the following command at the top of the script :
Python
# importing module calc.py import calc print (add( 10 , 2 )) |
Output:
12
The from import Statement
Python’s from statement lets you import specific attributes from a module. The from .. import .. has the following syntax :
Python3
# importing sqrt() and factorial from the # module math from math import sqrt, factorial # if we simply do "import math", then # math.sqrt(16) and math.factorial() # are required. print (sqrt( 16 )) print (factorial( 6 )) |
Output:
4.0 720
The from import * Statement
The * symbol used with the from import the statement is used to import all the names from a module to a current namespace.
Syntax:
from module_name import *
The use of * has it’s advantages and disadvantages. If you know exactly what you will be needing from the module, it is not recommended to use *, else do so.
Python3
# Import built-in module random from random import * print ( dir (random)) |
Output:
[‘__call__’, ‘__class__’, ‘__delattr__’, ‘__dir__’, ‘__doc__’, ‘__eq__’, ‘__format__’, ‘__ge__’, ‘__getattribute__’, ‘__gt__’, ‘__hash__’, ‘__init__’, ‘__init_subclass__’, ‘__le__’, ‘__lt__’, ‘__module__’, ‘__name__’, ‘__ne__’, ‘__new__’, ‘__qualname__’, ‘__reduce__’, ‘__reduce_ex__’, ‘__repr__’, ‘__self__’, ‘__setattr__’, ‘__sizeof__’, ‘__str__’, ‘__subclasshook__’, ‘__text_signature__’]
The dir() function
The dir() built-in function returns a sorted list of strings containing the names defined by a module. The list contains the names of all the modules, variables, and functions that are defined in a module.
Python3
# Import built-in module random import random print ( dir (random)) |
Output:
[‘BPF’, ‘LOG4’, ‘NV_MAGICCONST’, ‘RECIP_BPF’, ‘Random’, ‘SG_MAGICCONST’, ‘SystemRandom’, ‘TWOPI’, ‘_BuiltinMethodType’, ‘_MethodType’, ‘_Sequence’, ‘_Set’, ‘__all__’, ‘__builtins__’, ‘__cached__’, ‘__doc__’, ‘__file__’, ‘__loader__’, ‘__name__’, ‘__package__’, ‘__spec__’, ‘_acos’, ‘_bisect’, ‘_ceil’, ‘_cos’, ‘_e’, ‘_exp’, ‘_inst’, ‘_itertools’, ‘_log’, ‘_pi’, ‘_random’, ‘_sha512’, ‘_sin’, ‘_sqrt’, ‘_test’, ‘_test_generator’, ‘_urandom’, ‘_warn’, ‘betavariate’, ‘choice’, ‘choices’, ‘expovariate’, ‘gammavariate’, ‘gauss’, ‘getrandbits’, ‘getstate’, ‘lognormvariate’, ‘normalvariate’, ‘paretovariate’, ‘randint’, ‘random’, ‘randrange’, ‘sample’, ‘seed’, ‘setstate’, ‘shuffle’, ‘triangular’, ‘uniform’, ‘vonmisesvariate’, ‘weibullvariate’]
Code Snippet illustrating python built-in modules:
Python3
# importing built-in module math import math # using square root(sqrt) function contained # in math module print (math.sqrt( 25 )) # using pi function contained in math module print (math.pi) # 2 radians = 114.59 degreees print (math.degrees( 2 )) # 60 degrees = 1.04 radians print (math.radians( 60 )) # Sine of 2 radians print (math.sin( 2 )) # Cosine of 0.5 radians print (math.cos( 0.5 )) # Tangent of 0.23 radians print (math.tan( 0.23 )) # 1 * 2 * 3 * 4 = 24 print (math.factorial( 4 )) # importing built in module random import random # printing random integer between 0 and 5 print (random.randint( 0 , 5 )) # print random floating point number between 0 and 1 print (random.random()) # random number between 0 and 100 print (random.random() * 100 ) List = [ 1 , 4 , True , 800 , "python" , 27 , "hello" ] # using choice function in random module for choosing # a random element from a set such as a list print (random.choice( List )) # importing built in module datetime import datetime from datetime import date import time # Returns the number of seconds since the # Unix Epoch, January 1st 1970 print (time.time()) # Converts a number of seconds to a date object print (date.fromtimestamp( 454554 )) |
Output:
5.0 3.14159265359 114.591559026 1.0471975512 0.909297426826 0.87758256189 0.234143362351 24 3 0.401533172951 88.4917616788 True 1461425771.87 1970-01-06
This article is contributed by Gaurav Shrestha. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above. If you like GeeksforGeeks and would like to contribute, you can also write an article and mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
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