When trying to generate a new invoice, the render fails because the temporary file is not written. Execution example: `$ accli invoice generate -t templates -o /tmp/ black_white issued_invoices/2017-09.yaml` Result: `rubtmpb8V5bR.tex: Emergency stop. Traceback (most recent call last): File "/home/joseluis/repos/accli/testenv/bin/accli", line 11, in <module> load_entry_point('accli==0.0.1', 'console_scripts', 'accli')() File "/home/joseluis/repos/accli/testenv/lib/python3.5/site-packages/accli/cli.py", line 39, in main return args.func(args) File "/home/joseluis/repos/accli/testenv/lib/python3.5/site-packages/accli/commands/invoice.py", line 107, in run check_output(cmd, shell=True) File "/usr/lib/python3.5/subprocess.py", line 316, in check_output **kwargs).stdout File "/usr/lib/python3.5/subprocess.py", line 398, in run output=stdout, stderr=stderr) subprocess.CalledProcessError: Command 'cat /tmp/tmplyatpjv4 | rubber-pipe -I templates/black_white/tex -d > 2017-09.pdf' returned non-zero exit status 2` Debugging accli, I can see that the intermediate file `/tmp/tmplyatpjv4` is created, but it is empty when the subprocess command execution is performed