'Returns the atoms that form the current object.
Examples
>>> from sympy.abc import x, y
>>> from sympy.matrices import Matrix
>>> Matrix([[x]])
Matrix([[x]])
>>> _.atoms()
{x}'

def atoms(self, *types):

    types = tuple(((t if isinstance(t, type) else type(t)) for t in types))
    if (not types):
        types = (Atom,)
    return self._eval_atoms(*types)
