text: def add(a,b):
      return a+b
  def sub(a,b):
      return a-b 
  def mul(a,b):
      return a*b 
  def divide(a,b):
      return a/b 
  def si(P,R,T): # si means simple Interest
      return (P*R*T)/100       
  def ci(P,R,T): # ci means compound Interest 
      return P*pow((1+R/100),T)             
  def sqr(num):
      return num**2
  def st(num):
      return num**0.5
  
  # It is like a package were all funtions are preserved
  print(add(10,66)) # Here by calling the function we can execute that functions
  