Open specified object
obj_id = H5O.open(loc_id,relname,lapl_id)
obj_id = H5O.open(loc_id,relname,lapl_id) opens
an object specified by location identifier and relative path name.
lapl_id is the link access property list associated
with the link pointing to the object. If default link access properties
are appropriate, this can be passed in as 'H5P_DEFAULT'.
fid = H5F.open('example.h5'); obj_id = H5O.open(fid,'g3','H5P_DEFAULT'); H5O.close(obj_id); H5F.close(fid);