virtualbox-python: Problem creating medium

When tried to create a medium using:

vbox = virtualbox.VirtualBox()

bus = virtualbox.library.StorageBus(2)

vm.add_storage_controller("SATA", bus)

access_mode = virtualbox.library.AccessMode(2)

device_type = virtualbox.library.DeviceType(3)

medium = vbox.create_medium("VDI", vm_hd_path, access_mode, device_type)

medium.create_base_storage()

medium = vbox.open_medium(vm_hd_path, device_type, access_mode, True)

vm.attach_device(vm_hd_name, 0, 0, device_type, medium)

I got the following error:

Traceback (most recent call last): File “environment_configuration.py”, line 268, in <module> enviroment.method() File “environment_configuration.py”, line 211, in method medium = vbox.create_medium(“VDI”, vm_hd_path, access_mode, device_type) File “/usr/local/lib/python2.7/dist-packages/virtualbox/library.py”, line 7289, in create_medium in_p=[format_p, location, access_mode, a_device_type_type]) File “/usr/local/lib/python2.7/dist-packages/virtualbox/library_base.py”, line 170, in _call method = self._search_attr(name) File “/usr/local/lib/python2.7/dist-packages/virtualbox/library_base.py”, line 151, in _search_attr raise AttributeError(“Failed to find attribute %s in %s” % (name, self)) AttributeError: Failed to find attribute createMedium in <virtualbox.library_ext.vbox.IVirtualBox object at 0x7f03459e5650>