how to define function in python

1#Letters, Nums,
2#& underscores
3#only, can't	=7  
4#start w/ num	|		  _ 5 is the default value if no
5# 	  |			|		 |  value is passed
6#	  v         v        v
7def funcName(param1, param2=5): #The colon terminates func header 
8	str(param1) #Typecasting is temparary
9    strVar = str(param1) # To make typecast perma, assign to var
10    param1 = param2 # 5 is passed to param1 
11    return param1 # 5 is returned
12#	  ^      ^
13#     |		 |_ return value is optional, if no return value, func 
14  #Optional		will end returning to func call
15  #return
16
17x = funcName(7)
18print(x) # prints 5

1OK, basically def function() is a block where you will have one task that you can repeat all over again in the code to make it look short and clean

1def function():
2  print('This is a basic function')
3  
4function()
5// Returns 'This is a basic function'
6
7def add(numA, numB):
8  print(numA+numB)
9  
10add(1,2)
11// Returns 3
12
13def define(value):
14  return value
15
16example = define('Lorem ipsum')
17print(example)
18// Returns 'Lorem ipsum'
19
20

1#A function is a block of code which only runs when it is called.
2#You can pass data, known as parameters, into a function.
3#following is a simple function
4def exmple_of_function():
5  print("Hello from a function")
6
7example_of_function()

1def name():#name of the def(function);
2  print("Hallo, World!")#Output is Hallo, World!;
3  
4name()#Name of the def, the programm will jump to the def;
5
6#output:
7#Hallo, World!

1def function_name():
2  pass