Number System:

• Binary Number System

• Octal Number System

• Decimal Number System

• Hexadecimal Number System
  
  

1. Binary Number System
   - represents by 0 or 1.
   - base or radix is 2.
   - If we wanted to store a number in a python variable, that number should sharts with 0b OR 0B.

  x = ob0110
  print(x)

  x = oB0110
  print(x)

      2. Octal System
         - represents by 0 to 7.
          - base or radix is 8.
          - If we wanted to store a number in a python variable, that number should sharts with 0o OR 0O.

        x = 0o0234
      print(x)

  x = 0O0110
  print(x)

    3. Decimal System
      - represents by 0 to 9.
        - base or radix is 10.

        x = 578
          print(x)

     4. Hexadecimal System
        - represents by 0 to 9 and a to f OR A to F .
        - base or radix is 16.
        - If we wanted to store a number in a python variable, that number should sharts with 0x OR 0X.

          x = 0xA56
          print(x)

           x = 0xa56
          print(x)

Input/Output in Python

    -  There are built in functions to perform input and output operation.

• #Input = input()
  #Output = print()

   a = 30

   str = “Hello” #This is the static assignment but when we want to assign a dynamic assignment it means runtime.

name = input("Enter the Name")

age    = input("Enter the age")

place = input("Enter the place")

print("Name is",name,"\n","Age is",age,"\n","Place is",place)

print() method Syntax:
print(obj*,sep=’ ’,end=’\n’)

Syntax of the print() function

 print(obj*, ..., sep=' ', end='\n', file=sys.stdout, flush=False) 

print() Parameters

• objects - object to the printed. * indicates that there may be more than one object

• sep - objects are separated by sep. Default value: ' '

• end - end is printed at last.  Default value: '\n'

• file - here you can mention the file in which you would like to write or append the output of the print function.  By default is sys.stdout will be used which prints objects on the screen.

• flush - If True, the stream is forcibly flushed. Default value: False

#print with objects

print("C","C++","Java","Swift","Python")

#print with objectsAndSep

print("C","C++","Java","Swift","Python",sep="\n")

#print with end

str1 = "We are going"

str2 = "to learn Python"

print(str1); print(str2)

print(str1, end=" "); print(str2)

#print with file

file = open('print.txt','a+') #a,+ are the mode

print(str1,str2,file=file)

file.close()

import time

print('Please enter your email-id : ', end=' ')

#print('Please enter your email-id : ', end=' ', flush=True) #run this to see the difference and comment out the above line of code.

time.sleep(5)

'''If you run the above lines of code in the terminal, you will notice that the prompt string does not show up until the sleep timer ends and the program exits. However, if you add flush=True in the print function, you will see the prompt, and then you will have to wait for 5 seconds for the program to finish.'''

format():

a = "javascript"

b = "java"

print(a,"is a scripting language",b,"is Object oriented programming language")

print("{0} is a scripting language.{1} is a Object oriented programming language".format(a,b))

F string: 

check

f"x = {x}, y = {y} "

 Python Modules 

help(“modules”)
  - Module is simply a file that contains variables,functions and Classes that we can use in any other files using import. 

  -  There are two types of modules
    1.  User Defined Module

2. Build In Module
   
   

1. User Defined Module

1. Create one .py file. ex. mymodule.py and write below code

   def sayHelloTo(name):

           print(“Hello”,name)

2. Create second .py file. ex. moduleexample.py and write below code

  import  mymodule
    print(mymodule.sayHelloTo(“Chaitanya”))

3. Run code in terminal:

  python3 moduleexample.py
    o/p: Hello Chaitanya

       Whenever we run the file if you check our file location there is one folder created with name __pycache__.

What is __pycache__?

When you run a program in python, the interpreter compiles it to bytecode first (this is an oversimplification) and stores it in the __pycache__ folder. If you look in there you will find a bunch of files sharing the names of the .py files in your project's folder, only their extensions will be either .pyc or .pyo. These are bytecode-compiled and optimized bytecode-compiled versions of your program's files, respectively.

As a programmer, you can largely just ignore it... All it does is make your program start a little faster. When your scripts change, they will be recompiled, and if you delete the files or the whole folder and run your program again, they will reappear (unless you specifically suppress that behavior)

you can suppress it by starting the interpreter with the -B flag, for example

     python3 -B  moduleexample.py

Access Variable from module
  a. Create a dictionary in mymodule.py.
     deatilInfo = {"name":"Chaitanya","age":"27"}

   b. Access dictionary in other file moduleexample.py like below

       print("Your Age is:",mymodule.deatilInfo["age"])

Alias Module

  We are able to change the name of module in other file using as keyword at the time of import the module. See below
  import  mymodule as my
   print("Your Age is:",my.deatilInfo["age"])

2. Built-in Modules

   There are several build in modules available in python.

     import platform
    print(help("modules"))
      print(platform.system()) # print darwin for mac Because the core of Mac OS X is the Darwin OS. try uname in  terminal

using  from .. import :

  We have an option to import only some parts from a module, by using the from keyword.
from math import sqrt,
print(sqrt(25))

using dir() function.

dir() function to know the names and attributes of a module.
print(dir(mymodule))