title: How to fix "ERROR: Failed building wheel for pytorch3d" error on Colab?
body: <p>I'm trying to use a very cool machine learning Colab.  <a href="https://colab.research.google.com/drive/1eQLZrNYRZMo9zdnGGccE0hFswGiinO-Z?usp=sharing" rel="nofollow noreferrer">https://colab.research.google.com/drive/1eQLZrNYRZMo9zdnGGccE0hFswGiinO-Z?usp=sharing</a> Running their steps as is, I keep getting <code>ERROR: Failed building wheel for pytorch3d</code>.</p>
  <p>After much Googling, I've tried for instance replacing the install line with</p>
  <p><code>!pip install 'git+https://github.com/facebookresearch/pytorch3d.git@stable'</code></p>
  <p>and also</p>
  <p><code>!pip install pytorch3d</code></p>
  <p>The former doesn't work. The latter makes another issue arise:</p>
  <p><code>&quot;ImportError: /usr/local/lib/python3.6/dist-packages/pytorch3d/_C.cpython-36m-x86_64-linux-gnu.so: undefined symbol: _ZNK2at6Tensor7is_cudaEv&quot;</code></p>
  <p>I also tried doing <code>!pip install torch==1.6.0</code> which causes</p>
  <pre><code>Traceback (most recent call last):
    File &quot;./meshrcnn/demo/demo.py&quot;, line 11, in &lt;module&gt;
      from detectron2.data import MetadataCatalog
    File &quot;/usr/local/lib/python3.6/dist-packages/detectron2/data/__init__.py&quot;, line 4, in &lt;module&gt;
      from .build import (
    File &quot;/usr/local/lib/python3.6/dist-packages/detectron2/data/build.py&quot;, line 14, in &lt;module&gt;
      from detectron2.structures import BoxMode
    File &quot;/usr/local/lib/python3.6/dist-packages/detectron2/structures/__init__.py&quot;, line 6, in &lt;module&gt;
      from .keypoints import Keypoints, heatmaps_to_keypoints
    File &quot;/usr/local/lib/python3.6/dist-packages/detectron2/structures/keypoints.py&quot;, line 6, in &lt;module&gt;
      from detectron2.layers import interpolate
    File &quot;/usr/local/lib/python3.6/dist-packages/detectron2/layers/__init__.py&quot;, line 3, in &lt;module&gt;
      from .deform_conv import DeformConv, ModulatedDeformConv
    File &quot;/usr/local/lib/python3.6/dist-packages/detectron2/layers/deform_conv.py&quot;, line 10, in &lt;module&gt;
      from detectron2 import _C
  ImportError: /usr/local/lib/python3.6/dist-packages/detectron2/_C.cpython-36m-x86_64-linux-gnu.so: undefined symbol: _ZN6caffe28TypeMeta21_typeMetaDataInstanceISt7complexIdEEEPKNS_6detail12TypeMetaDataEv
  </code></pre>
  <p>Have done <code>!pip install mmcv-full===1.2.1 -f https://download.openmmlab.com/mmcv/dist/cu101/torch1.7.0/index.html</code> to try fixing that and the error persists.</p>
  <p>Does anyone have ideas for how to make the Colab environment work?</p>