def definite_crop(img, bbox):
  """crop an image.

  Args:
      img: `ndarray`, input image
      bbox: list, with crop co-ordinates and width and height
          e.g.: [x, y, width, height]

  Returns:
      returns cropped image
  """
  img = img[:, bbox[0]:bbox[2], bbox[1]:bbox[3]]
  return img