def iter_halfs_bond(graph):
for atom1, atom2 in graph.edges:<EOL><INDENT>try:<EOL><INDENT>affected_atoms1, affected_atoms2 = graph.get_halfs(atom1, atom2)<EOL>yield affected_atoms1, affected_atoms2, (atom1, atom2)<EOL><DEDENT>except GraphError:<EOL><INDENT>continue<EOL><DEDENT><DEDENT>
Select a random bond (pair of atoms) that divides the molecule in two