set cosmo in FastPMParticleSource #1
Description
need to address case of cosmo not None
https://github.com/rainwoodman/fastpm-python/blob/master/fastpm/nbkit.py#L13
{{ message }}
need to address case of cosmo not None
https://github.com/rainwoodman/fastpm-python/blob/master/fastpm/nbkit.py#L13