Modern Python Standard Library Cookbook

How to do it...

For this recipe, the following steps are to be performed:

1. Take the following set of elements:

>>> values = [ 5, 3, 1, 7 ]

2. Looking up an element in the sequence can be done through the in operator:

>>> 5 in values
True

3. Sorting can be done through the sorted function:

>>> sorted_value = sorted(values)
>>> sorted_values
[ 1, 3, 5, 7 ]

4. Once we have a sorted container, we can actually use the bisect module to find contained entries faster:

def bisect_search(container, value):
    index = bisect.bisect_left(container, value)
    return index < len(container) and container[index] == value

5. bisect_search can be used to know whether an entry is in the list, much like the in operator did:

>>> bisect_search(sorted_values, 5)
True