Module has not attribute

I have a problem installing modules. when updating I have this error:

 Traceback (most recent call last):
      File "bin/trytond-admin", line 23, in <module>
      File "/home/jmeuh/Workspace/hg_trytond-5.8/trytond/trytond/", line 53, in run
      File "/home/jmeuh/Workspace/hg_trytond-5.8/trytond/trytond/", line 152, in init
      File "/home/jmeuh/Workspace/hg_trytond-5.8/trytond/trytond/", line 105, in start
      File "/home/jmeuh/Workspace/hg_trytond-5.8/trytond/trytond/modules/", line 345, in register_classes
      File "/home/jmeuh/Workspace/hg_trytond-5.8/trytond/trytond/modules/country/", line 11, in register
    AttributeError: module '' has no attribute 'Country'

Installation source : hg clone -b 5.8 hg_trytond-5.8

Thanks for help

Did you run correctly the .hooks/link_modules ?
It looks like you are missing files or having non consistent state in the repository.

No, but a few months ago I installed it without any problem.

What is .hooks / link_modules used for?
How to run it?

Check the README in tryton-env repository.

Thanks for the answer which solves the problem but the result does not have the one I am looking for. I am using a script to generate the links of a chosen module and its dependencies. I think he’s the one who’s breaking the problem.