Transform element numbers into symbols

elements.py

from collections import OrderedDict

elements = OrderedDict([(1, 'H'),
             (2, 'He'),
             (3, 'Li'),
             (4, 'Be'),
             (5, 'B'),
             (6, 'C'),
             (7, 'N'),
             (8, 'O'),
             (9, 'F'),
             (10, 'Ne'),
             (11, 'Na'),
             (12, 'Mg'),
             (13, 'Al'),
             (14, 'Si'),
             (15, 'P'),
             (16, 'S'),
             (17, 'Cl'),
             (18, 'Ar'),
             (19, 'K'),
             (20, 'Ca'),
             (21, 'Sc'),
             (22, 'Ti'),
             (23, 'V'),
             (24, 'Cr'),
             (25, 'Mn'),
             (26, 'Fe'),
             (27, 'Co'),
             (28, 'Ni'),
             (29, 'Cu'),
             (30, 'Zn'),
             (31, 'Ga'),
             (32, 'Ge'),
             (33, 'As'),
             (34, 'Se'),
             (35, 'Br'),
             (36, 'Kr'),
             (37, 'Rb'),
             (38, 'Sr'),
             (39, 'Y'),
             (40, 'Zr'),
             (41, 'Nb'),
             (42, 'Mo'),
             (43, 'Tc'),
             (44, 'Ru'),
             (45, 'Rh'),
             (46, 'Pd'),
             (47, 'Ag'),
             (48, 'Cd'),
             (49, 'In'),
             (50, 'Sn'),
             (51, 'Sb'),
             (52, 'Te'),
             (53, 'I'),
             (54, 'Xe'),
             (55, 'Cs'),
             (56, 'Ba'),
             (57, 'La'),
             (58, 'Ce'),
             (59, 'Pr'),
             (60, 'Nd'),
             (61, 'Pm'),
             (62, 'Sm'),
             (63, 'Eu'),
             (64, 'Gd'),
             (65, 'Tb'),
             (66, 'Dy'),
             (67, 'Ho'),
             (68, 'Er'),
             (69, 'Tm'),
             (70, 'Yb'),
             (71, 'Lu'),
             (72, 'Hf'),
             (73, 'Ta'),
             (74, 'W'),
             (75, 'Re'),
             (76, 'Os'),
             (77, 'Ir'),
             (78, 'Pt'),
             (79, 'Au'),
             (80, 'Hg'),
             (81, 'Tl'),
             (82, 'Pb'),
             (83, 'Bi'),
             (84, 'Po'),
             (85, 'At'),
             (86, 'Rn'),
             (87, 'Fr'),
             (88, 'Ra'),
             (89, 'Ac'),
             (90, 'Th'),
             (91, 'Pa'),
             (92, 'U'),
             (93, 'Np'),
             (94, 'Pu'),
             (95, 'Am'),
             (96, 'Cm'),
             (97, 'Bk'),
             (98, 'Cf'),
             (99, 'Es'),
             (100, 'Fm'),
             (101, 'Md'),
             (102, 'No'),
             (103, 'Lr'),
             (104, 'Rf'),
             (105, 'Db'),
             (106, 'Sg'),
             (107, 'Bh'),
             (108, 'Hs'),
             (109, 'Mt'),
             (110, 'Ds'),
             (111, 'Rg'),
             (112, 'Cn'),
             (113, 'Uut'),
             (114, 'Fl'),
             (115, 'Uup'),
             (116, 'Lv'),
             (117, 'Uus'),
             (118, 'Uuo')])