text: # relative imports are somewhat tricky
  # always run it as python module when running at the terminal
  # current package
  from . import area
  # sibling package
  from ..sub_package_1 import foo
  # parent package
  from .. import sub_package_1
  
  """ 
  NOTE: runing this as a script will give you following error: 
  
  ImportError: attempted relative import with no known parent package
  
  run as python -m <parent_package>.<sub_package>.<module_name>
  
  directory structure - 
  parent_package
      sub_package_1
          module_1
      sub_package_2
          module_2
  
  """
  
  print("area of circle is:", round(area.area_circle(5), 2))
  
  def vol_cyl(height, radius):
      return height * area.area_circle(radius)
  
  print("volume of cylinder is:", round(vol_cyl(1, 5), 2))
  