Issue with running on Google Colab

Hi there.
I'm trying to use polyscope on Google Colab, but after installing with pip and running the following code:

import polyscope as ps

# Initialize polyscope
ps.init()

### Register a point cloud
# `my_points` is a Nx3 numpy array
ps.register_point_cloud("my points", my_points)

### Register a mesh
# `verts` is a Nx3 numpy array of vertex positions
# `faces` is a Fx3 array of indices, or a nested list
ps.register_surface_mesh("my mesh", verts, faces, smooth_shade=True)

# Add a scalar function and a vector function defined on the mesh
# vertex_scalar is a length V numpy array of values
# face_vectors is an Fx3 array of vectors per face
ps.get_surface_mesh("my mesh").add_scalar_quantity("my_scalar", 
        vertex_scalar, defined_on='vertices', cmap='blues')
ps.get_surface_mesh("my mesh").add_vector_quantity("my_vector", 
        face_vectors, defined_on='faces', color=(0.2, 0.5, 0.5))

# View the point cloud and mesh we just registered in the 3D UI
ps.show()

I just get the following error:

---------------------------------------------------------------------------

RuntimeError                              Traceback (most recent call last)

<ipython-input-36-bdac230fc77e> in <module>()
      2 
      3 # Initialize polyscope
----> 4 ps.init()
      5 
      6 ### Register a point cloud

/usr/local/lib/python3.6/dist-packages/polyscope/core.py in init(backend)
     10     cwd_before = os.getcwd() # see note below
     11 
---> 12     psb.init(backend)
     13 
     14     # NOTE: For some reason I do not understand, calling psb.init() changes the working directory, causing e.g. writes to relative file paths to write to unexpected locations afterwards.

RuntimeError: [polyscope] ERROR: Failed to initialize glfw

Any idea why is this happening?

polyscope/core.py の init() から始め、続いて「Failed to initialize glfw.」と報告する backend の初期化を追跡します。Google Colab で最小限の ps.init() 呼び出しを再現し、修正可能な初期化問題なのか、サポート対象外の環境なのかを判断します。動作が解決されるか、制限事項が明確に文書化されれば完了です。