Goodbye everyone, doing a proof of concept at home I found that when using the command "pip3 install -r requeriments.txt" I missed the following error:
No command 'pip3' found, did you mean: Command 'pip' from package 'python-pip' (universe) pip3: command not found
Apparently it is a bug related to python and then I installed everything necessary to suggest the use of the pip command but still I am still giving the same error.
I'm on a virtual machine with ubuntu 12.04 (x64). Could someone explain the fault?