Open3d: “示例/Python/Basic/half_edge_mesh.py”中的“TypeError：crop()：不兼容的函数参数”

描述错误
我无法运行示例half_edge_mesh.py 。 #1218之后总是抛出

RPly: Unable to open file
[Open3D WARNING] Read PLY failed: unable to open file: ../../TestData/sphere.ply
Traceback (most recent call last):
  File "examples/Python/Basic/half_edge_mesh.py", line 28, in <module>
    mesh = mesh.crop(bbox)
TypeError: crop(): incompatible function arguments. The following argument types are supported:
    1. (self: open3d.open3d.geometry.TriangleMesh, min_bound: numpy.ndarray[float64[3, 1]], max_bound: numpy.ndarray[float64[3, 1]]) -> open3d.open3d.geometry.TriangleMesh

Invoked with: geometry::TriangleMesh with 0 points and 0 triangles., geometry::AxisAlignedBoundingBox

在#1218（仍为0.8.0版本）之前，它抛出

RPly: Unable to open file
[Open3D WARNING] Read PLY failed: unable to open file: ../../TestData/sphere.ply
Traceback (most recent call last):
  File "examples/Python/Basic/half_edge_mesh.py", line 26, in <module>
    het_mesh = o3d.geometry.HalfEdgeTriangleMesh.create_from_triangle_mesh(mesh)
AttributeError: type object 'open3d.open3d.geometry.HalfEdgeTriangleMesh' has no attribute 'create_from_triangle_mesh'

再现
重现行为的步骤：

1. cd open3d
2. python3示例/Python/Basic/half_edge_mesh.py
3. 查看错误

预期行为
这个例子应该有效。

环境（请填写以下信息）：

• 操作系统：OSX Mojave
• Python版本：3.7
• Open3D 版本：0.8.0
• 这是远程工作站吗？：否
• 你是如何安装 Open3D 的？：conda

附加上下文
我试图将示例文件half_edge_mesh.py到与TestData/sphere.ply相同的文件夹并编辑路径。 警告[Open3D WARNING] Read PLY failed: unable to open file: ../../TestData/sphere.ply消失了，但 TypeError 或 AttributeError 仍然存在。