ALTER Command:
(i) The ALTER command is used to alter the table structure like adding a column, renaming the existing column, change the data type of any column or size of the column or delete the column from the table. It is used in the following way:
(ii) ALTER TABLE <table-name>  ADD  <column-name><data type> <size>;
(iii) To add a new column "Address" of type 'char' to the Student table, the command is used as
(iv) ALTER TABLE Student ADD Address char;
To modify, existing column of table, the ALTER TABLE command can be used with MODIFY clause like wise:
(v) ALTER < table-name > MODIFY < column-name > < data type > < size >;
ALTER TABLE Student MODIFY Address char (25);
(vi) The above command will modify the address column of the Student table to now hold 25 characters.
(vii) The ALTER command can be used to rename an existing column in the following way:
(viii) ALTER < table-name > RENAME old-column- name TO new-column-name;
(ix) For example to rename the column Address to City, the command is used as :
(x) ALTER TABLE Student RENAME Address TO City;
(xi) The ALTER command can also be used to remove a column or all columns. for example to remove a particular column, the DROP COLUMN is used with the ALTER TABLE to remove a particular field, the command can be used as:
ALTER < table-name > DROP COLUMN < column-name >;
(xii) To remove the column City from the Student table, the command is used as :
ALTER TABLE Student DROP COLUMN City;

str1=input ("Enter a string:")
str2="aAeEiloOuU"
v,c=0,0
for i in str1:
if i in str2:
v+=1
else:
c+=1
print ("The given string contains {} vowels and {} consonants".format(v.c))
Output:
Enter a string: Tamilnadu School Education.
The given string contains 11 vowels and 15 consonants.

# python program to find HCF
def HCF (x,y):
if(x > y):
s = y
else:
s = x
for I inrange (1, s + 1):
if ((x % I = = 0) and (y% i = = 0)):
hcf = i
return hcf
x = int (input ("Enter Number 1"))
y = int (input ("Enter Number 2"))
print (HCF (x, y))

//Now select File ➝ New in Notepad and type the Python program
# Save the File as classpy.py
# Python classpy.py -i inheri_cpp command to execute c++ program
Python Program:
import sys, os, getopt
def main (argv):
cpp_file ="
exe_file ="
opts.args= getopt.getopt (argv, "i:",['ifile='])
for o, a in opts:
1ifile. ("'-"1", --ifile"):
cpp_file = a + '.cpp'
exe_file = a + '.exe'
run (cppfile, exe_file)
def run(cpp_file, exe_file):
print ("Compiling" + cpp_file)
os.system ('g++ ' + cpp_file + '-o' + exe_file)
print ("Running" + exe_file)
print ("------------------- ")
print
os.system (exe_file)
print
if __name__ =='__main__"
main (sys.argv[1:])

//Now select File⟶New in Notepad and type the Python program
# Save the File as transpose.py. Program that compiles and executes a .cpp file
# Python tanspose.py -i trans_cpp
Python Program:
import sys, os, getopt
def main(argv):
cpp_file = "
exe_file = "
opts,args = getopt.getopt(argv, "i:",['ifile='])
for o, a in opts:
if o in ("-i", "< -ifile"):
cpp_file = a + '.cpp'
exe_file = a + '.exe'
run(cpp_file, exe_file)
defrun( cpp _file, exe_file):
print("Compiling" + cpp_file)
'os.system ('g++' + cpp_file + '-o' + exe_file)
print("Running" + exe_file)
print(" -------------------")
print
os.system( exe_file)
print
if __name__ =='__main__"
main( sys.argv[ 1:])

#Now select File￫New in Notepad and type the Python program
# Save the File as pali.py . Program that compiles and executes a .cpp file
# Python c:\pyprg\pali.py -i c:\pyprg\pali_cpp import sys, os, getopt
def main(argv):
cpp_file ="
exe_file = "
opts, args= getopt.getopt(argv, "i:",['ifile='])
for o, a in opts:
if o in ("-i", "--ifile"):
cpp_file = a + '.cpp'
exe_file = a + '.exe'
run(cpp_file, exe_file)
def run(cpp_file, exe_file):
print("Compiling" + cpp_file)
os.system('g++' + cpp_file + '-o' + exe_file)
print("Running" + exe_file)
print("-----------------")
print
os.system(exe_file)
print
if __name__ =='__main__': # program starts executing from here
main(sys.argv[ 1:])

class Circle:
pi=3.14
def _init_(self.radius):
self.radius=radius
def area(self):
return Circle. pi*(self.radius**2)
def circumference(self):
return 2*Circle.pi*self.radius
r=int(input("Enter Radius: "))
Ce=Circle(r)
print("The Area =",C.area())
print("The Circumference =", Cxircumferencet())

(i) for i in range (5, 0,-1):
for j in range (1, i + 1):
print (i, end =' ')
print (end = '\n')
i+ = 1
(ii) for i in range (5, 0, -1):
for j in range (1, i + 1):
print (j end =' ')
print (i, end = '\n')
i+ = 1

i=1
while (i < = 6):
for j in range (1,i):
print (j,end='\t')
print (end='\n')
i+=1
Output:
1
1 2
1 2 3
1 2 3 4
1 2 3 4 5

To write the CSV file with custom quote characters, by registering new dialects using csv. register_dialect( ) class of csv module.
Example:
import csv
csvData = [['SNO",Items'], ['1",Pen'], ['2",Book'], ['3"Pencil']]
csv.register_dialect('myDialect',delimiter = '|',
quotechar = '"', quoting=csv.QUOTE_ALL)
with open('c:\\pyprg\\ch13\\quote.csv', 'w') as csvFile:
writer = csv.writer(csvFile, dialect='myDialect')
writer. writerows( csvData)
print("writing completed")
csvFile.close( )

Import csv
#opening the csv file which is in different location with read mode
f=open("c:\\pyprg\\ch13ample5.csv",'r')
#reading the File with the help of csv.reader( )
readFile=csv.reader(f)
#printing the selected column
for col in readFile:
print col[0],col[3]
f.close ( )
Sample5.csv File in Excel

Program:
Num = []
for x in range(1, 11):
Num.append(x)
print("The list of numbers from 1 to 10 = ",Num)
for index, i in enumerate(Num):
if(i%2==0):
del Num[index]
print("The list after deleting even numbers = ", Num)
Output:
The list of numbers from 1 to 10 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
The list after deleting even numbers =. [1, 3, 5, 7, 9]

Program:
n=[]
for x in range (1, 11)
n = append (x)
for x, i in enumerate (n):
if(i %2! = 0):
del n [x]
print (n)

(i) Access control is a security technique that regulates who or what can view or use resources in a computing environment.
(ii) It is a fundamental concept in security that minimizes risk to the object.
(iii) In other words access control is a selective restriction of access to data. IN Object oriented programming languages it is implemented through access modifiers.
(iv) Classical object-oriented languages, such as C++ and Java. control the access to class members by public, private and protected keywords.
(v) Private members of a class are denied access from the outside the class. They can be handled only from within the class.
(vi) Public members (generally methods declared in a class) are accessible from outside the class. The object of the same class is required to invoke a public method. This arrangement of private instance variables and public methods ensures the principle of data encapsulation.
(vii) Protected members of a class are accessible from within the class and are also available to its sub-classes. No other process is permitted access to it. This enables specific resources of the parent class to be inherited by the child class.
(viii) Python doesn't have any mechanism that effectively restricts access to any instance variable or method. Python prescribes a convention of prefixing the name of the variable or method with single or double underscore to emulate the behaviour of protected and private access specifiers.
(ix) All members in a Python class are public by default. whereas by default in C++ and java they are private. Any member can be accessed from outside the class environment in Python which is not possible in C++ and java.