[MacPorts] #62661: py39-pyusb: "No backend available" error at runtime

[MacPorts]

#62661: py39-pyusb: "No backend available" error at runtime
------------------------------+------------------------
  Reporter:  programmingkidx  |      Owner:  reneeotten
      Type:  defect           |     Status:  closed
  Priority:  Normal           |  Milestone:
 Component:  ports            |    Version:  2.6.4
Resolution:  fixed            |   Keywords:
      Port:  py-pyusb         |
------------------------------+------------------------

Comment (by programmingkidx):

 Ok, after running 'sudo port selfupdate', I was able to see version 1.1.1.
 After importing the usb module like this: import usb.core
 I ran 'help(usb._version)'. It showed this:

 {{{
 Help on module usb._version in usb:

 NAME
     usb._version

 DESCRIPTION
     # coding: utf-8
     # file generated by setuptools_scm
     # don't change, don't track in version control

 DATA
     version = '1.1.1'
     version_tuple = (1, 1, 1)

 FILE
 /opt/local/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9
 /site-packages/usb/_version.py
 }}}

 I am sure I am using the right version.

 I then ran this code:
 dev = usb.core.find(idVendor=0x0d8c,idProduct=0x0008)

 I saw this error again:
 {{{
 Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
   File
 "/opt/local/Library/Frameworks/Python.framework/Versions/3.9/lib/python3.9
 /site-packages/usb/core.py", line 1299, in find
     raise NoBackendError('No backend available')
 usb.core.NoBackendError: No backend available
 }}}

 The USB device I am using is plugged in and detected by Mac OS 11. I was
 able to verify this in the 'System Information' application.

 Please let me know if you need anything. Thanks.

-- 
Ticket URL: <https://trac.macports.org/ticket/62661#comment:6>
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