AttributeError: 'str' object has no attribute 'namespaces'

[kevinkle]

https://sentry.io/superphy/spfy/issues/562192633/

AttributeError: 'str' object has no attribute 'namespaces'
  File "rq/worker.py", line 700, in perform_job
    rv = job.perform()
  File "rq/job.py", line 500, in perform
    self._result = self.func(*self.args, **self.kwargs)
  File "modules/phylotyper/phylotyper.py", line 83, in phylotyper
    markerseqs = MarkerSequences(loci, job_id, job_turtle, job_ectyper_datastruct_vf, redis_conn)
  File "modules/phylotyper/sequences.py", line 140, in __init__
    self.graph = g + fetch_job(job_id, redis_conn).result + fetch_job(job_turtle, redis_conn).result + fetch_job(job_ectyper_datastruct_vf, redis_conn).result
  File "rdflib/graph.py", line 572, in __add__
    list(self.namespaces()) + list(other.namespaces())):

AttributeError: 'str' object has no attribute 'namespaces'