[Health] No module named qrcode

[Amidu Sila]

Gentlemen,
After  installing a Gnu Health in a new server, during the creation of the database I got the following message:

Error creating database!

Can't create the database, caused by an unknown reason.

If there is a database created, it could be broken. Maybe drop this database! Please check the error message for possible informations.

Error message:

No module named qrcode

For your information I did the installation of the following modules successfully, after the tryton_health_profile one :

 trytond_health_services, trytond_health_reporting, trytond_health_history, trytond_health_nursing, trytond_health_stock, trytond_health_icu, trytond_health_mdg6, trytond_health_qrcodes, 
trytond_health_icd10pcs and trytond_health_inpatient_calendar

Please can you help me to overcome the situation?
Thank you all in advance
Amidu