input: Write a function to compute the area of a circle with the given radius. If the given radius is less than or equal to 0 then return -1.
  import math
  
  def area_circle(radius):
   if radius <= 0:
   return -1
   return math.pi * (radius ** 2)
  
  assert area_circle(5) == 78.54
  assert area_circle(-3) == -1
  assert area_circle(0) == -1
output: import math
  
  def area_circle(radius):
   if radius <= 0:
   return -1
   return math.pi * (radius ** 2)