$ py15
Python 3.7.5 (default, May 26 2020, 08:53:41)
[GCC 5.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import torch
>>> torch.utils.cmake_prefix_path
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module 'torch.utils' has no attribute 'cmake_prefix_path'
>>> torch.__version__
'1.5.0'

and
# py15 is the python that install torch1.5
$ py15  -c 'import torch;print(torch.utils.cmake_prefix_path)'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
AttributeError: module 'torch.utils' has no attribute 'cmake_prefix_path'