Python intro

• Python is a popular programming language.
• Python can be used on a server to create web applications.

Why Python

Python use cases

• web development
• DevOps
• data science
• data analysis
• machine learning
• finance industry

Python variables

• Variables are containers for storing data values.
• Python has no command for declaring a variable.
• A variable is created the moment you first assign a value to it.

Example program to take input from the user and print to console.

# Get user first_name and last_name
first_name=input("Enter your first_name") # Takes the input from the user and stores in the variable first_name
last_name=input("Enter your last_name") # Takes the input from the user and stores in the variable last_name

# display the names in the line
print(first_name + last_name )
dob=input("Please , enter your DOB:") # Takes the input dob from user
print(dob)
# course name
course_name=input("Please, Enter your course name :")
print(course_name)
# UK_resident
uk_resident =input ("Are you a resident of UK ?")
print(uk_resident)

Output of the console is

Python Comments

• Comments can be used to explain Python code.
• Comments can be used to make the code more readable.

Python Data Types

• Built-in Data Types
• In programming, data type is an important concept.
• Variables can store data of different types, and different types can do different things.
• Python has the following data types built-in by default, in these categories:
  • Text Type: str
  • Numeric Types: int, float, complex
  • Sequence Types: list, tuple, range
  • Mapping Type: dict
  • Set Types: set, frozenset
  • Boolean Type: bool
  • Binary Types: bytes, bytearray, memoryview

How to setup git+github using SSH key pair

• Install Git in your local machine
• Create a github account
• We can connect local host to the github by twoways
  • SSH (Secure Shell)
  • HTTPS
• Step 1 :Generate ssh keys on localhost
  • Open git bash terminal
    • Go to .ssh directory using the command cd ~/.ssh
    • If the .ssh directory does not exist , create it using the command mkdir .ssh
    • Now go to the directory using the command cd ~/.ssh
    • To generate the key use the command ssh-keygen -t rsa -b 4096 -C "[email protected]"
    • It will ask to enter the file to save the key.Don't give any file name, just click enter and enter
    • Give command ls to list the files in .ssh
    • We will have key-pair (2 files) id_rsa ,id_rsa.pub.
      • One with .pub extension is public key
      • One without .pub extension is called private key
• Step 2 :Keep the private key on local host inside the .ssh folder
• Step 3 :Copy the public key into your repository on github
  • Use the command cat id_rsa.pub to open the public key file.
    • Once opened,copy the contents of the file
    • Go to the Github account settings--> SSH and GPG Keys-->Click on New SSH Key-->Give some title and paste the key and click on "Add SSH Key".
    • It will ask the passwork to confirm
• After doing the above three steps we can push anything to Github from our local machine and we can clone anything from Github to pur local machine.

Points to be noted

• Always open Pycharm as administrator.
• Make sure you copy the public key without spaces and paste into repository

Steps to push to github from local machine

• create README.md file in pycharm in local machine
• Add the notes
• Use the below commands to push into the github
• git init
• git commit
• git commit -m "first commit"
• git add .
• git branch -M main
• git remote add origin [email protected]:meghanasrividya/git_github_setup.git
• git push -u origin main

Git and GitHUb

• add changes to our Git -Hub repo - the changes we made on localhost

• git add filename or git add .

• git commit -m "new markdown guide added"

• now let's send this new data to github

• git push -u origin main

• git status

• git add .gitignore then add all dependencies that you do not want to push

This change is done on Github

Cheat Sheet of Git Bash

start a working area (see also: git help tutorial)
   clone     Clone a repository into a new directory
   init      Create an empty Git repository or reinitialize an existing one

work on the current change (see also: git help everyday)
   add       Add file contents to the index
   mv        Move or rename a file, a directory, or a symlink
   restore   Restore working tree files
   rm        Remove files from the working tree and from the index

examine the history and state (see also: git help revisions)
   bisect    Use binary search to find the commit that introduced a bug
   diff      Show changes between commits, commit and working tree, etc
   grep      Print lines matching a pattern
   log       Show commit logs
   show      Show various types of objects
   status    Show the working tree status

grow, mark and tweak your common history
   branch    List, create, or delete branches
   commit    Record changes to the repository
   merge     Join two or more development histories together
   rebase    Reapply commits on top of another base tip
   reset     Reset current HEAD to the specified state
   switch    Switch branches
   tag       Create, list, delete or verify a tag object signed with GPG

collaborate (see also: git help workflows)
   fetch     Download objects and refs from another repository
   pull      Fetch from and integrate with another repository or a local branch
   push      Update remote refs along with associated objects

Introduction of Data Types and Operators

• + - * /

Comparison Operators

• > greater than
• < less than
• == True or False
• >= Greater than or equal
• <= Less than or equal

a=24
b=16
print(a+b)# outcome added value of a & b
print(a-b)# outcome subtraction of b from a
user_age=18
# comparison
print(a>b)# outcome be True
print(a<b)# outcome be False
print(a==b)

# Boolean builtin methods in Python- Boolean Methods
# - DRY do not repeat yoyrself print("")
greeting ="Hello World!"
print(greeting)
print(greeting.isalpha())# This method checks whether there are only alphabets in the string
print(greeting.islower())# This method checks whether there are only lower case alphabets in the string
print(greeting.startswith("H"))# This method checks whtehr the string starts with "H"
print(greeting.endswith("!")) # checks if it ends with letter
print(greeting.isdigit())# This method checks whether there are only digit in the string

greeting="Hello WOrld!"
print(greeting[-12:-6])
print(greeting[0:5])

white_space="lot's of spaces at the end               "
print(len(white_space))
#strip() removes the white spaces at the end
print(len(white_space.strip()))

Example_text ="here's is sOme text with loT's of text"
print(Example_text.count("text"))# This method counts the word that taken as argument in the string
print(Example_text)
print(Example_text.lower())# This method converts the string to lower case alphabets
print(Example_text.upper())# This method converts the string to upper case alphabets
print(Example_text.capitalize())# This method capitalise the first letter of each word in the string
print(Example_text.replace("with",","))# This method uses to replace particular word with other word which is given as argument in the string

Concatenation & Casting

• adding strings together
• casting/converting one data type to another data type

first_name= "Meghana" # string
last_name= "Aenugu"
salary= 40 # int

print(first_name + last_name)
print(first_name+ " "+ last_name + " " +str(salary))

Example to write the program to take inputs from the user and display back to him

 Get user first_name and last_name
first_name=input("Enter your first_name") # Takes the input from the user and stores in the variable first_name
last_name=input("Enter your last_name") # Takes the input from the user and stores in the variable last_name

# display the names in the line
print(first_name + last_name )
dob=input("Please , enter your DOB:") # Takes the input dob from user

#salary
salary=input("Please, enter your salary")
# course name
course_name=input("Please, Enter your course name :")

# UK_resident
uk_resident =input ("Are you a resident of UK ?")

address = input("Could you please enter the address")
hobbies= input("Could you please enter your hobbies")

print( " Hello " + first_name +" "+ last_name+"Your details are:")
print("\n Full name: "+first_name +" "+ last_name)
print("\n DOB: "+dob)
print("\n salary : "+ str(salary))
print("\n Course name: "+course_name)
print("\n UK resident :"+ uk_resident)
print("\n address: "+ address)
print("\n hobbies: " +hobbies)

Data Collections

# Data Collections
# Lists
# Tuples
# Dict
# Lists

# syntax list_name=["addhh","asdfg","2erfghj"]

# Apply DRY
shopping_list =["ketchup","fanta","eggs","bread"]
# indexing    =    0           1     2      3
print(shopping_list)
print(type(shopping_list))
shopping_list.append("chicken")
#print()# add an item to the list
print(shopping_list)
shopping_list[2]="ice cream"
print(shopping_list)
# find out how to remove an item from the list
# find out how to remove fanta from the list
shopping_list.remove("fanta") # use remove method to delete an item from the list
print(shopping_list)
shopping_list.pop(1)
print(shopping_list)
multiple_type=[1 ,2,3,"one","two","three"]
print(multiple_type)
print(multiple_type[2])

# Tuple

# Immutable - cant be changed - edited- add

# user_details = DOB - country name - city name
# Syntax ("")

essentials = ("milk","paracetamol","drinks")
print(essentials)
print(type(essentials))
# what is the diff between Lists & Tuples

Python Practise

Python Operators

Python Lists

Python Tuples

#What is a Dictionary?
# How to manage data using Dictionaries
# How does it work as key= value
# Syntax { "name": "Sparta"}

# store student's data-name,course_name,progress,completed_lessons

student_1 = {
    "keys":"values",
    "name": "Meghana",
    "stream":"DevOps",
    "completed_lessons":4,
    "completed _lessons_names":["lists","tuples","strings"]
}
print(student_1)
print(type(student_1))
print(student_1["stream"])# This will display the value saved inside stream
#print/display completed_lessons_names
print(student_1["completed _lessons_names"])
#print/display completed_lessons_names index 0 means lists
print(student_1["completed _lessons_names"][0])# displays lists
print(student_1["completed _lessons_names"][1])# displays tuples
print(student_1["completed _lessons_names"][2])# displays strings

print(student_1)
print(type(student_1))
print(student_1["stream"])# This will display the value saved inside stream
#print/display completed_lessons_names
print(student_1["completed _lessons_names"])
#print/display completed_lessons_names index 0 means lists
print(student_1["completed _lessons_names"][0])# displays lists
print(student_1["completed _lessons_names"][1])# displays tuples
print(student_1["completed _lessons_names"][2])# displays strings
student_1["completed_lessons"]=3
print(student_1["completed_lessons"])
#delete an item from the list of completed _lessons/key
student_1["completed _lessons_names"].remove("OOP")
print(student_1["completed _lessons_names"])
#Dict BuiltIn Methods
#display keys only or values
#keys() values()
print(student_1.keys())

# display values only from student_1
print(student_1.values())