MODULES IN PYTHON
In this article, we will learn about creating and importing self created modules in Python. We will explore different ways of exporting python modules as well and learn how to use the built-in modules in python.
What are Modules in Python?
A module is a python file with a ‘.py’ extension which consists of functions, statements and variables. The reason we use modules is to break down big programs into simpler and smaller ones. We can reuse module files anytime as well.
Let’s create a module file and name it as ‘my_code.py’, and create a function inside it.
def my_function():
print("This is a module file")
my_function()
Importing a Module
Now that we created a module file, let’s save it in the same directory where our main python file is stored. Now let’s suppose we are inside our main.py file; now it’s time to use the import statement to import the my_code.py file:
import my_code my_code.my_function()
When the python interpreter sees an import statement, it imports the module file if the module is present in the same directory, otherwsie it will show an error. Once the module is imported then you can call the relevant function name that you want to use.
my_code.my_function()
Note: Whenever you want to use the function from your module file, then you have to follow the syntax: modulename.functionname().
‘From’ in Import Statement
Sometimes the module file is gonna have more than one block of code so Python lets you import a specific block from your module, let’s say that you have a file named info_modules.py and it has two dictionaries named ‘person_1’ and ‘person_2’ and you want to import ‘person_1’ in your main program.
person_1 = { 'name': "hira", 'age': '29', 'gender': 'Female', }
person_2 = { 'name': "Smith", 'age': '29', 'gender': 'Male', }
Importing person_1 in the main.py file using from statement
from my_code import person_1 print(person_1)
Output will be:
{'name': 'hira', 'age': '29', 'gender': 'Female'}
Note: once you have specifically imported the function, variable or statement in your main program then you don’t have use modulename.functionname() syntax while calling it in your main file. Just call the name directly with from statement.
Renaming a Module using Alias
You can rename a module as well in python. Let’s say you want to call your info_modules as info as a short form so that you can have flexibility, for example:
import info_modules as info print(info.person_1)
Output will be:
{'name': 'hira', 'age': '29', 'gender': 'Female'}
Built in Modules
There is an extensive list of all the built-in modules that python supports, each caters a different functionality and usage depending on what we want to calculate. In order to see the list of modules python supports just type:
print(help('modules'))
Output will be:
IPython _weakrefset heapq secrets __future__ _winapi hmac select _abc abc html selectors _ast aifc http setuptools _asyncio antigravity idlelib shelve _bisect argparse imaplib shlex _blake2 array imghdr shutil _bootlocale ast imp signal _bz2 asynchat importlib simplegeneric _codecs asyncio ind site _codecs_cn asyncore inspect six _codecs_hk atexit io smtpd _codecs_iso2022 audioop ipaddress smtplib _codecs_jp autoreload ipython_genutils sndhdr _codecs_kr backcall itertools socket _codecs_tw base64 jedi socketserver _collections bdb json sqlite3 _collections_abc binascii keyword sre_compile _compat_pickle binhex lib2to3 sre_constants _compression bisect linecache sre_parse _contextvars builtins locale ssl _csv bz2 logging stat _ctypes cProfile lzma statistics _ctypes_test calendar macpath storemagic _datetime cgi mailbox string _decimal cgitb mailcap stringprep _distutils_findvs chunk marshal struct _dummy_thread cmath math subprocess _elementtree cmd mimetypes sunau _functools code mmap symbol _hashlib codecs modulefinder sympyprinting _heapq codeop msilib symtable _imp collections msvcrt sys _io colorama multiprocessing sysconfig _json colorsys netrc tabnanny _locale compileall nntplib tarfile _lsprof concurrent nt telnetlib _lzma configparser ntpath tempfile _markupbase contextlib nturl2path test _md5 contextvars numbers tests _msi copy opcode textwrap _multibytecodec copyreg operator this _multiprocessing crypt optparse threading _opcode csv os time _operator ctypes parser timeit _osx_support curses parso tkinter _overlapped cythonmagic pathlib token _pickle dataclasses pdb tokenize _py_abc datetime pickle trace _pydecimal dbm pickleshare traceback _pyio decimal pickletools tracemalloc _queue decorator pip traitlets _random difflib pipes tty _sha1 dis pkg_resources turtle _sha256 distutils pkgutil turtledemo _sha3 doctest platform types _sha512 dummy_threading plistlib typing _signal easy_install poplib unicodedata _sitebuiltins email posixpath unittest _socket encodings pprint urllib _sqlite3 ensurepip profile uu _sre enum prompt_toolkit uuid _ssl errno pstats venv _stat faulthandler pty warnings _string filecmp py_compile wave _strptime fileinput pyclbr wcwidth _struct fnmatch pydoc weakref _symtable formatter pydoc_data webbrowser _testbuffer fractions pyexpat winreg _testcapi ftplib pygments winsound _testconsole functools queue wsgiref _testimportmultiple gc quopri xdrlib _testmultiphase genericpath random xml _thread getopt re xmlrpc _threading_local getpass reprlib xxsubtype _tkinter gettext rlcompleter zipapp _tracemalloc glob rmagic zipfile _warnings gzip runpy zipimport _weakref hashlib sched zlib
