https://www.tutorialspoint.com/python3/index.htm

#!/usr/bin/python3
 
# output
print ("Hello, Python!")
print(x, end=" ")  # Appends a space instead of a newline in Python 3
 
# input
x = input("something:")
 
# raise exception
raise IOError("file error") #this is the recommended syntax in Python 3

# Quotation in Python
word = 'word'
sentence = "This is a sentence."
paragraph = """This is a paragraph. It is
made up of multiple lines and sentences."""

# Simple Assignment
counter = 100          # An integer assignment
miles   = 1000.0       # A floating point
value   = 3e+26J       # A complex
name    = "John"       # A string
 
# Multiple Assignment
a = b = c = 1
a, b, c = 1, 2, "john"
 
# deletion
a, b, c = 1, 2, "john"

str = 'Hello World!'
 
print (str)          # Prints complete string
print (str[0])       # Prints first character of the string
print (str[2:5])     # Prints characters starting from 3rd to 5th
print (str[2:])      # Prints string starting from 3rd character
print (str * 2)      # Prints string two times
print (str + "TEST") # Prints concatenated string

list = [ 'abcd', 786 , 2.23, 'john', 70.2 ]
tinylist = [123, 'john']
 
print (list)          # Prints complete list
print (list[0])       # Prints first element of the list
print (list[1:3])     # Prints elements starting from 2nd till 3rd 
print (list[2:])      # Prints elements starting from 3rd element
print (tinylist * 2)  # Prints list two times
print (list + tinylist) # Prints concatenated lists

tuple = ( 'abcd', 786 , 2.23, 'john', 70.2  )
tinytuple = (123, 'john')
 
print (tuple)           # Prints complete tuple
print (tuple[0])        # Prints first element of the tuple
print (tuple[1:3])      # Prints elements starting from 2nd till 3rd 
print (tuple[2:])       # Prints elements starting from 3rd element
print (tinytuple * 2)   # Prints tuple two times
print (tuple + tinytuple) # Prints concatenated tuple

dict = {}
dict['one'] = "This is one"
dict[2]     = "This is two"
 
tinydict = {'name': 'john','code':6734, 'dept': 'sales'}
 
print (dict['one'])       # Prints value for 'one' key
print (dict[2])           # Prints value for 2 key
print (tinydict)          # Prints complete dictionary
print (tinydict.keys())   # Prints all the keys
print (tinydict.values()) # Prints all the values

#Data Type Conversion
int(x [,base]) #Converts x to an integer. The base specifies the base if x is a string.
float(x) # Converts x to a floating-point number.
complex(real [,imag]) # Creates a complex number.
str(x) # Converts object x to a string representation.
repr(x) # Converts object x to an expression string.
eval(str) # Evaluates a string and returns an object.
tuple(s) # Converts s to a tuple.
list(s) # Converts s to a list.
set(s) # Converts s to a set.
dict(d) # Creates a dictionary. d must be a sequence of (key,value) tuples.
frozenset(s) # Converts s to a frozen set.
chr(x) # Converts an integer to a character.
unichr(x) # Converts an integer to a Unicode character.
ord(x) # Converts a single character to its integer value.
hex(x) # Converts an integer to a hexadecimal string.
oct(x) # Converts an integer to an octal string.

# Python Arithmetic Operators
c = a % b  # Modulus
c = a ** b # Exponent
c = a // b # Floor Division
 
# Python Membership Operators
x in y
x not in y
 
# Python Identity Operators
x is y
x is not y

# if statement
if expression:
   statement(s)
 
# if else statement
if expression:
   statement(s)
else:
   statement(s)
 
# nested if statements
if expression1:
   statement(s)
elif expression:
   statement(s)
else:
   statement(s)
 
# Single Statement if
if ( var  == 100 ) : print ("Value of expression is 100")

# while loop
while expression:
   statement(s)
 
while count < 5:
   count = count + 1
else:
   print (count, " is not less than 5")
 
 
# for loop
for iterating_var in sequence:
   statements(s)
 
>>> range(5)
range(0, 5)
>>> list(range(5))
[0, 1, 2, 3, 4]
 
fruits = ['banana', 'apple',  'mango']
for index in range(len(fruits)):
   print ('Current fruit :', fruits[index])
 
for num in numbers:
   if num%2 == 0:
      print ('the list contains an even number')
      break
else:
   print ('the list doesnot contain even number')
 
# Loop Control Statements
break
continue
pass

# Iterators
list = [1,2,3,4]
it = iter(list) # this builds an iterator object
print (next(it)) #prints next available element in iterator
 
# Iterator object can be traversed using regular for statement
for x in it:
   print (x, end=" ")
 
# or using next() function
while True:
   try:
      print (next(it))
   except StopIteration:
      sys.exit() #you have to import sys module for this

# Generators
 
import sys
def fibonacci(n): #generator function
   a, b, counter = 0, 1, 0
   while True:
      if (counter > n): 
         return
      yield a
      a, b = b, a + b
      counter += 1
f = fibonacci(5) #f is iterator object
 
while True:
   try:
      print (next(f), end=" ")
   except StopIteration:
      sys.exit()

#!/usr/bin/python
 
class Employee:
   'Common base class for all employees'
   empCount = 0
 
   def __init__(self, name, salary):
      self.name = name
      self.salary = salary
      Employee.empCount += 1
 
   def displayCount(self):
     print "Total Employee %d" % Employee.empCount
 
   def displayEmployee(self):
      print "Name : ", self.name,  ", Salary: ", self.salary
 
"This would create first object of Employee class"
emp1 = Employee("Zara", 2000)
"This would create second object of Employee class"
emp2 = Employee("Manni", 5000)
emp1.displayEmployee()
emp2.displayEmployee()
print "Total Employee %d" % Employee.empCount

# Built-In Class Attributes
print "Employee.__doc__:", Employee.__doc__
print "Employee.__name__:", Employee.__name__
print "Employee.__module__:", Employee.__module__
print "Employee.__bases__:", Employee.__bases__
print "Employee.__dict__:", Employee.__dict__

# Class Inheritance
class Parent:        # define parent class
   parentAttr = 100
   def __init__(self):
      print "Calling parent constructor"
 
   def parentMethod(self):
      print 'Calling parent method'
 
   def setAttr(self, attr):
      Parent.parentAttr = attr
 
   def getAttr(self):
      print "Parent attribute :", Parent.parentAttr
 
class Child(Parent): # define child class
   def __init__(self):
      print "Calling child constructor"
 
   def childMethod(self):
      print 'Calling child method'
 
c = Child()          # instance of child
c.childMethod()      # child calls its method
c.parentMethod()     # calls parent's method
c.setAttr(200)       # again call parent's method
c.getAttr()          # again call parent's method

# Overriding Methods
class Parent:        # define parent class
   def myMethod(self):
      print 'Calling parent method'
 
class Child(Parent): # define child class
   def myMethod(self):
      print 'Calling child method'
 
c = Child()          # instance of child
c.myMethod()         # child calls overridden method