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# -*- coding: utf-8 -*-
"""
httpbin.utils
~~~~~~~~~~~~~~~
Utility functions.
"""
import random
import bisect
def weighted_choice(choices):
"""Returns a value from choices chosen by weighted random selection
choices should be a list of (value, weight) tuples.
eg. weighted_choice([('val1', 5), ('val2', 0.3), ('val3', 1)])
"""
values, weights = zip(*choices)
total = 0
cum_weights = []
for w in weights:
total += w
cum_weights.append(total)
x = random.uniform(0, total)
i = bisect.bisect(cum_weights, x)
return values[i]
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