InvokeMethod error when trying to copy disk

Hello,

I'm trying to copy a disk using VirtualDiskManager.CopyVirtualDisk:

destSpec = vim.VirtualDiskManager.VirtualDiskSpec()
 destSpec.diskType = "eagerZeroedThick"
 destSpec.adapterType = "busLogic"
 dc = self.get_obj([vim.Datacenter], dc)
 task = vim.VirtualDiskManager.CopyVirtualDisk(
            sourceName=source_path,
            sourceDatacenter=dc,
            destName=dest_path,
            destDatacenter=dc,
            destSpec=destSpec
   )

Here, sourceDatacenter and desDatacenter are valids, sourceName and destName are strings in the form of "[Datastore] path/to/disk"

I get the following error:

File "/usr/lib/python2.7/site-packages/pyVmomi/VmomiSupport.py", line 574, in call
return self.f(*args, **kwargs)
TypeError: _InvokeMethod() takes at least 2 arguments (1 given)

I originally used pyvmomi-6.0.0.2016.6 and I upgraded to 6.5.0.2017.5.post1, without any change.

Is there a way I can troubleshoot this ? I tried to find in the documentation what I missed but found nothing, is it a known issue ?

Regards,
Grégoire

Start with the supplied VirtualDiskManager.CopyVirtualDisk call and inspect VmomiSupport.py around _InvokeMethod, then compare the invocation signature with the pyVmomi API documentation for VirtualDiskSpec and datacenter arguments. Reproduce the TypeError using the provided Python snippet; done means the cause of the argument mismatch is identified and the issue has a verified invocation or documented limitation.