FUNCTIONS#2

############ Functions and Docstrings Tutorial #################
	# Function helps in code reuseability
	##########################################
	## Example of built in function
	a = 9
	b = 8
	# Sum is a inbuilt function in Python
	# takes tuple or list (more, general Iterables) as input
	c = sum((a,b))
	print(c) # Output : 17
	##########################################
	## Example of user defined function
	## The keyword def introduces a function definition.
	# It must be followed by the function name and
	# the parenthesized list of formal parameters.
	# The statements that form the body of the function
	# start at the next line, and must be indented.
	def function1():
	print("Hello you are in function 1")
	function1() # Output : Hello you are in function 1
	##### Functions with Parameter & Return Statement ####
	# The 'return' statement returns with a value from a function.
	# 'return' without an expression argument returns None
	# if no 'return' statement used in function ,
	# then function returns None
	print(function1())
	# Output : Hello you are in function 1 (due to function call)
	# : None (due to no return statement)
	## Functions with parameters
	def function2(a,b):
	print("You are in function 2,","Sum :",a+b)
	function2(5,7)
	# Output :You are in function 2, Sum : 12
	def function3(a,b):
	average = (a+b)/2
	print("Average :",average)
	function3(5,7)
	# Output : Average : 6.0
	# If we want to store value calculated by function in a variable
	# We have to use return statement
	def function4(a,b):
	average = (a+b)/2
	# print("Average :",average)
	return average
	val = function4(5,7)
	print(val)
	# Output : 6.0
	################ Doc strings ##################
	# Used to store information about function
	# """ Documentation """ or ''' Documentation '''
	# # This is not a comment but docstring ...
	# ...if written as first line in function
	# written elsewhere in function treated as comment
	def function5(a,b):
	'''This is a function which calculates average of two numbers'''
	average = (a+b)/2
	return average
	print(function5.__doc__)
	# Output : This is a function which calculates average of two numbers
	# docstring is helpful to know about functions
	# in diiferent imported modules
	# Also if we have large no. of functions
	# we can use docstring to know about function