code: def sliceable(dim, pad=0):
      """
      collapse outer dimensions into one and preserve inner dimension
      this allows for easy cpu operations in numpy
      """
      dim0 = np.prod(dim[:-1]) + pad
      return (dim0, dim[-1])
  
file_path: neon/tests/test_backend_pool_layer.py
imports: import itertools
  import numpy
  import pytest
  from neon import logger
  from utils import allclose_with_out
label_desc: Use image node_id 1 for calling a global function with example usage: sliceable(dim, pad) and returns: dim0,  dim