Parallel client going out of scope closes connections with active output objects

[pkittenis]

Describe the bug Parallel client going out of scope closes connections with active output objects.

To Reproduce

Steps to reproduce the behavior:

output = ParallelClient(['localhost']).run_command('echo me')
print(list(output[0].stdout))

Output can be truncated.

Expected behavior Output can be read in its entirety while output objects are in scope.

Actual behaviour Cannot read complete output.

Additional information parallel-ssh: 2.5.3 ssh2-python: 0.22.0