Any reason why Atom __init__ doesnt enforce coordiates as numpy array

It took me one day to realize that :

atom = PDB.Atom.Atom('O', [x,y,z] , 0, 100 , " ", str(grid_cnt)[:1], grid_cnt, element = "H")

resi1.add(atom)

works but then

atom1 -atom2 fails because I need [x,y,z] to be a numpy array instead of a list (using a structure parsed with PDB.PDBParser

and doing parsedatom - myatom works even if my coords are a list).

Any reason why Atom instance accept __init__ values without checking their type ?