This document discusses file handling in Python. It explains that files are used to permanently store data and outlines the common file operations of opening, reading/writing, and closing. It then provides details on functions for opening files, reading/writing data, getting file metadata, and closing files. Additional topics covered include reading large files, using JSON and XML modules to load and parse file data, displaying HTML files, and interacting with Excel files.

2.  Files are named locations on disk to store related
information. They are used to permanently store
data in a non-volatile memory.
 The following is the order operation on files:
1. Open
2. Read or Write
3. Close

3.  open() function is used to open a file, which
returns a file object – used to call other support
methods associated with it.
fileObject = open(file_name [, access_mode][, buffering])
 close() method is used to close the file.
fileObject.close()

4.  file.name - Returns name of the file.
 file.mode - Returns access mode with which file
was opened.
 file.closed - Returns true if file is closed, false
otherwise.

5.  fileObject.read([count])
 fileObject.readline()
 fileObject.readlines()
 fileObject.write()

6.  fileObject.tell()
 fiileObject.seek(offset)

7.  readlines() method appends each line to the list and then
returns the entire list it will be time-consuming if the file size
is extremely large say in GB.
 The input() method of fileinput module can be used to read
large files.
fileinput.input(“filename”)
 Open the file in a ‘with’ block as it automatically closes the
file as soon as the entire block executes.
with open(“filename”) as file

8.  JavaScript Object Notation(JSON) is a script file
which is made of text in a programming language is
used to store and transfer the data.
 The text in JSON is done through quoted-string which
contains the value in key-value mapping within { }.
 Python has a built-in package called json, which can be
used to work with JSON data.

9.  The JSON package has json.load() function that loads the JSON content
from a JSON file into a dictionary.
json.load(file_object)
 The JSON package in Python has a function called json.dumps() that helps
in converting a dictionary to a JSON object
json_object = json.dumps(dictionary, indent)
file_object.write(json_object)
 Another way of writing JSON to a file is by using json.dump() method.
json.dump(dictionary,file_object)

10.  XML stands for eXtensible Markup Language. XML is
a text-based markup language designed to store and
transport data.
 Python comes with the ElementTree library that
provides several functions to read and manipulate the
XMLs.
 To use the ElementTree module, we need to import
xml.etree.ElementTree

11.  To load XML file use parse method.
ET.parse(source,parser)
 To know the root element use getroot().

13.  In order to display the HTML file as a python output, we will
be using the codecs library. This library is used to open files
which have a certain encoding. It takes a
parameter encoding which makes it different from the built-in
open() function.
 In Python, webbrowser module provides a high-level
interface which allows displaying Web-based documents to
users. The webbrowser module can be used to launch a
browser in a platform-independent manner

14.  Excel is a spreadsheet application which is developed
by Microsoft. It is an easily accessible tool to organize,
analyze, and store the data in tables.
 Python provides xlrd and openpyxl modules for excel
spreadsheet.
pip install xlrd
pip install openpyxl