gremlin-python tutorial test_000.py fails

[WolfgangFahl]

see http://wiki.bitplan.com/index.php/Gremlin_python#Connecting_to_Gremlin_enabled_graph_databases

To reproduce:

git clone https://github.com/WolfgangFahl/gremlin-python-tutorial
git checkout 75b7116d9ea29ea4a8292dfa2cafcf9d51936927
cd gremlin-python-tutorial
scripts/runOrientDB 
ln -f OrientDB.yaml server.yaml
python3 test_000.py

test_000.py

# see https://github.com/WolfgangFahl/gremlin-python-tutorial/blob/master/test_001.py
from tutorial import remote

# initialize a remote traversal
g = remote.RemoteTraversal().g()

# test the number of vertices
def test_LoadModern():
    remoteTraversal=remote.RemoteTraversal()
    remoteTraversal.load("tinkerpop-modern.xml")

# call the loadModern test
test_LoadModern()

error message

python3 test_000.py 
Traceback (most recent call last):
  File "test_000.py", line 13, in <module>
    test_LoadModern()
  File "test_000.py", line 10, in test_LoadModern
    remoteTraversal.load("tinkerpop-modern.xml")
  File "/Users/wf/source/python/gremlin-python-tutorial/tutorial/remote.py", line 33, in load
    g.V().drop().iterate()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/process/traversal.py", line 66, in iterate
    try: self.nextTraverser()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/process/traversal.py", line 71, in nextTraverser
    self.traversal_strategies.apply_strategies(self)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/process/traversal.py", line 573, in apply_strategies
    traversal_strategy.apply(traversal)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/driver/remote_connection.py", line 149, in apply
    remote_traversal = self.remote_connection.submit(traversal.bytecode)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/driver/driver_remote_connection.py", line 54, in submit
    results = result_set.all().result()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/concurrent/futures/_base.py", line 435, in result
    return self.__get_result()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/driver/resultset.py", line 90, in cb
    f.result()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/concurrent/futures/_base.py", line 428, in result
    return self.__get_result()
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/concurrent/futures/_base.py", line 384, in __get_result
    raise self._exception
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/concurrent/futures/thread.py", line 57, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/driver/connection.py", line 80, in _receive
    status_code = self._protocol.data_received(data, self._results)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/driver/protocol.py", line 97, in data_received
    return self.data_received(data, results_dict)
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/gremlin_python/driver/protocol.py", line 110, in data_received
    raise GremlinServerError(message["status"])
gremlin_python.driver.protocol.GremlinServerError: 599: null:none([])