Currently completion candidates returned by click are sorted in ZSH based on alphanumeric rules. This means that completions ['1', '2', '10'] would be displayed out of natural sort order as ['1', '10', '2']. Update the completion script to bring the sorting into Python where custom types can be sorted more appropriately. Note that the version of bash that ships with OS X is v3.2. The nosort option for complete was introduced in v4.4 This change should support both.