bidict_bidirectional_dictionary_forward_inverse_lookups.py

1from bidict import bidict
2
3# Create a bidict
4element_by_symbol = bidict({'H': 'hydrogen'})
5
6# Forward lookup
7assert element_by_symbol['H'] == 'hydrogen'
8
9# Inverse lookup
10assert element_by_symbol.inverse['hydrogen'] == 'H'
11
12# Add a new mapping
13element_by_symbol['He'] = 'helium'
14
15# Inverse lookup again
16assert element_by_symbol.inverse['helium'] == 'He'
17
18# Attempting to map a new key to an existing value raises a ValueDuplicationError
19# element_by_symbol['Li'] = 'hydrogen'  # This would raise an error