Install fails

When i was installing the package in colab, i have followed error info
Downloading https://test-files.pythonhosted.org/packages/91/e7/2bb3aeea86faadfe5f23adddf7f8d7375e70e390571da4da916c4e261c48/sklearn-0.0.post3.tar.gz (3.7 kB)
  error: subprocess-exited-with-error