File Handling:
==============
for programming purpose, files can be considered for the storage permanently.
==> files are classified into two types:
	1) Text Files/Character file ==> .txt
	2) Binary Files

Note:
=====
	Every file must be defined with some extension.
	Ex: image files ==> .jpg/.jpeg/.png etc.
	audio files ==> .mp3/.ong
	video files ==> .3gpp/.mp4/.ong etc.

How to Open the files:
======================
about Text files:
=================
open():
======
	==> a built-in function, which we can use to open the existing file or to create the new file.
Syntax:
	file-object-name/file-pointer = open(file-with-extension, mode-of-the-file-in-quotes);
Here:
	file-with-extension ==> file name
	mode-of-the-file:
		write mode ==> w
		=================
# write mode
# w-mode can allow to open the existing file or
# also allow to create the file if the specified file is not existed.
# w-mode can write the data if the existing file is already with some data means: that old
# data can be vanished and re-write the new data from the beginning.

# opening the existing file in w-mode

fp = open("file1.txt","w")

# opening the new file in w-mode
fp1 = open("file2.txt","w")
======================================
		read mode ==> r
		================

r-mode (read mode)
# r-mode can help to open the existing file only
# it cannot be able to create the new file

# opening the existing file
# r-mode never vanish the old data from the existing file.
fp = open("file1.txt","r")

# opening the new file in r-mode
# error: File Not Found Error

fp1 = open("file3.txt","r")
==================================================
		append mode ==> a
		==================
# a-mode ==> append mode
# append can be able to add the data to existing data

# ld = [1,3,5,7,9]
#
# print(ld)
#
# ld.append(15)
#
# print(ld)

# a-mode can be able to open the existing file without vanishing the existing data

fp1 = open("file1.txt","a")

# a-mode can also able to create the new file
========================================================
		write-read mode ==> w+
		======================

# w+-mode ==> write + read

# w+-mode can be able to open the existing file as like w-mode by vanishing the old content

fp1 = open("file1.txt","w+")

fp1.write("Hi all. Good Evening.")

print(fp1.read())
============================================================
		read-write mode ==> r+
		======================
# r+-mode ==> read+write
# like r-mode: r+-mode also can be able to open the existing file only
fp1 = open("file1.txt","r+")
data = fp1.read()
print(data)

fp1.write("Welcome to Ashok IT.")
======================================================

		append-read mode ==> a+
		=======================
# a+-mode ==> append + write
# like a-mode,a+-mode can be able to open the existing file and new file

fp1 = open("file1.txt","a+")
fp2 = open("file5.txt","a+")

data2 = fp1.read()
print(data2)

fp1.write("\nWe are from Hyderabad")
#
data3 = fp1.read()
print(data3)
==========================================
		exclusive mode ==> x
		====================
# x-mode ==> Exclusive mode
# same as w-mode
# x-mode can always open the file for writing the data only in new file always.
# if file is already existed ==> file exist error
# fp1 = open("file1.txt","x")
# fp1 = open("file4.txt","x")
# fp1.read()
# fp1 = open("file6.txt","x")
# fp1.write("Hello All.")
# d = fp1.read()
# print(d)

fp1 = open("file7.txt","x")
fp1.write("Welcome to My Python Class.")
# d = fp1.read() ==> not possible with reading

# print(d)
====================================================
File object properties:
=======================
fp1 = open("file1.txt","r")

# some properties
print("Name of the file = ",fp1.name)
print("Mode of the file = ",fp1.mode)
print("is readable? = ",fp1.readable())
print("is writeable? = ",fp1.writable())

# when we have opened the file for handling.
# after the file operations we should close the file extensively using close()
# if you cannot be close the file extensively, the PVM can close this automatically.

print("Is file closed? = ",fp1.closed)
fp1.close()
print("Is file closed? = ",fp1.closed