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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _update_explicit_bucket_count(a_float, dist):
 """Adds `a_float` to `dist`, updating its explicit buckets. Args: a_float (float):
 a new value dist (:class:`endpoints_management.gen.servicecontrol_v1_messages.Distribution`):
 the Distribution being updated Raises: ValueError: if `dist` does not already have explict buckets defined ValueError: if there are not enough bucket count fields in `dist` """

    buckets = dist.explicitBuckets
    if buckets is None:
        raise ValueError(_BAD_UNSET_BUCKETS % (u'explicit buckets'))
    bucket_counts = dist.bucketCounts
    bounds = buckets.bounds
    if len(bucket_counts) < len(bounds) + 1:
        raise ValueError(_BAD_LOW_BUCKET_COUNT)
    bucket_counts[bisect.bisect(bounds, a_float)] += 1