Traceback (most recent call last):


 "<ipython-input-5-842ad8069d40>", line 1, in <module>

np.vstack([0] for _ in range(3))


 "/opt/venvs/py37/lib/python3.7/site-packages/numpy/core/overrides.py", line 151, in public_api

implementation, public_api, relevant_args, args, kwargs)


 "/opt/venvs/py37/lib/python3.7/site-packages/numpy/core/overrides.py", line 96, in array_function_implementation_or_override

return implementation(*args, **kwargs)


 "/opt/venvs/py37/lib/python3.7/site-packages/numpy/core/shape_base.py", line 260, in vstack

return _nx.concatenate([atleast_2d(_m) for _m in tup], 0)


 "/opt/venvs/py37/lib/python3.7/site-packages/numpy/core/overrides.py", line 151, in public_api

implementation, public_api, relevant_args, args, kwargs)


 "/opt/venvs/py37/lib/python3.7/site-packages/numpy/core/overrides.py", line 96, in array_function_implementation_or_override

return implementation(*args, **kwargs)


 "/opt/venvs/py37/lib/python3.7/site-packages/numpy/core/multiarray.py", line 193, in concatenate

return _multiarray_umath.concatenate(arrays, axis, out)
ValueError: need at least one array to concatenate

Traceback (most recent call last):


 "/opt/indico/.venv/lib/python2.7/site-packages/flask/app.py", line 1612, in full_dispatch_request

rv = self.dispatch_request()


 "/opt/indico/.venv/lib/python2.7/site-packages/flask/app.py", line 1598, in dispatch_request

return self.view_functions[rule.endpoint](**req.view_args)


 "/opt/indico/.venv/lib/python2.7/site-packages/indico/web/flask/util.py", line 114, in wrapper

return obj().process()


 "/opt/indico/.venv/lib/python2.7/site-packages/indico/web/rh.py", line 270, in process

res = self._do_process()


 "/opt/indico/.venv/lib/python2.7/site-packages/indico/web/rh.py", line 249, in _do_process

return self._process()


 "/opt/indico/.venv/lib/python2.7/site-packages/indico/modules/auth/controllers.py", line 97, in _process

response = multipass.handle_login_form(provider, form.data)


 "/opt/indico/.venv/lib/python2.7/site-packages/flask_multipass/core.py", line 459, in handle_login_form

response = provider.process_local_login(data)


 "/opt/indico/.venv/lib/python2.7/site-packages/flask_multipass/providers/sqlalchemy.py", line 55, in process_local_login

type(self).identifier_column == data['identifier']).first()


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2755, in first

ret = list(self[0:1])


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2547, in __getitem__

return list(res)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2855, in __iter__

return self._execute_and_instances(context)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/orm/query.py", line 2878, in _execute_and_instances

result = conn.execute(querycontext.statement, self._params)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 945, in execute

return meth(self, multiparams, params)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/sql/elements.py", line 263, in _execute_on_connection

return connection._execute_clauseelement(self, multiparams, params)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1053, in _execute_clauseelement

compiled_sql, distilled_params


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1189, in _execute_context

context)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1405, in _handle_dbapi_exception

util.reraise(*exc_info)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/engine/base.py", line 1182, in _execute_context

context)


 "/opt/indico/.venv/lib/python2.7/site-packages/sqlalchemy/engine/default.py", line 470, in do_execute

cursor.execute(statement, parameters)
ValueError: A string literal cannot contain NUL (0x00) characters.
