matrix.save_numeric(): Use io.open()
matrix.save_numeric(): Use io.open()

Built-in open() on Python2 does not support the input argument being an integer file descriptor.
MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3,MRtrix3/mrtrix3