(a) Check if PIP is Installed:
To check if PIP is already installed in our system, navigate our command line to the location of Python's script directory.
Command:
Python m pip install - U pip.
(b) To check PIP version:
To check the version of PIP in our system, type the command as:
C: \Users\Your Name\App Data\Local\Programs\Python\Python 36-32\Scripts> Pip--version.
(c) List packages:
To view the list of installed packages on our system, use the list command:
C:\Users\Your Name\App Data\Local\Programs\Python\Python 36-32\scripts> Pip list

Program: Display the records in descending order using python script
import mysqldb
db = mysqldb.connect ("local host", "user", "123", "organization")
cursor = db.cursor()
cursor.execute ("SELECT *FROM Employee ORDER BY Name DESC")
result = cursor.fetchall()
for row in results:
ENO = row[0], EmpName = row[1], EmpDept = row[2]
print ENO, EmpName, EmpDept
db.close()

welcome → module name
      ●      →  operator name
display() → definition name

Program: To read a csv file with comma (,)
#importing csv
import csv
#opening the csv file which is in different location with read mode
with open('c:\\Pyprg\ \sample1.csv', 'r') as F:
#other way to open the file is
f=('C:\\pyprg\\sample1.csv', 'r')
reader = csv.reader(F))
#printing each line of the Data row by row.
print (row)
F. close( )
Output:
['SNO','NAME', 'CITY']
['12101', 'RAM', 'CHENNAI']
['12102', 'LAVANYA' "TIRUCHY']
['12103', 'LAKSHMAN', 'MADURAI']

(i) The SAVEPOINT command is used to temporarily save a transaction so that you can rollback to the point whenever required.
(ii) The different states of our table can be saved at any time using different names and the rollback to that state can be done using the ROLLBACK command.
(iii) SAVEPOINT savepoint_name:
      UPDATE student SET Name = 'Mini' WHERE Admno=105;
      SAVEPOINT A;

Code:
class Sample:
def_init_(self, n1, n2):
            self._n1=nt
            self_n2-n2
def sum(self):
           print ("Class Variable 1:" self_n1)
           print ("Class Variable 2:", self_n2)
S=Sample (5,10)
S.sum()
Output:
Class Variable 1:5
Class Variable 2: 10
Sum: 15

(i) The format( ) function used with strings is very versatile and powerful function used for formatting strings.
(ii) The curly braces {} are used as placeholders or replacement fields which get replaced along with format( ) function.
Example:
num1 = int (input("Number 1:")) 
num2 = int (input("Number 2:")) 
print ("The, sum of {} and {} is {}". format (num1, num2, (num1 + num2)))
Output:
Number 1: 34
Number 2: 54
The sum of 34 and 54 is 88.

Code:
n=int(input("Enter the year"))
if(y%4==0):
         print ("Leap Year")
else:
         print ("Not a Leap Year")
Output:
Enter the year      2012
Leap Year

Syntax :
      while <condition>;
                statements block 1
       [else:
                statements block2]

(i) Time Factor -Time is measured by counting the number of key operations like comparisons in the sorting algorithm.
(ii) Space Factor -Space is measured by the maximum memory space required by the algorithm.

(i) In Python strings, the backslash "\" is a special character, also called the"escape" character.
(ii) It is used in representing certain whitespace characters: "\t" is a tab, "\n\" is a newline, and "\r" is a carriage return.
(iii) For example to print the message "It's raining", the Python command is
>>> print ("It \ 's raining")
It's raining
Python supports the following escape sequence characters.

(i) All programming languages permit functions to be nested. A function (method) within another function is called nested function.
(ii) A variable which is declared, inside a function which contains another function definition with in it, the inner function can also access the variable of the outer function. This scope is called enclosed scope.
(iii) When a compiler or interpreter search for a variable in a program, it first searches Local, and then searches Enclosing scopes. Consider the following example

1. Disp(); 2. a:=10 3. Disp1(): 4. print a 5. Disp1() 6. print a 7. Disp()

Entire program

Output of the program 10 10

(i) The class template specifies the interfaces to enable an object to be created and operated properly.
(ii) An object's attributes and behaviour is controlled by sending functions to the object.