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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_general_statistics(a_float, dist):
 """Adds a_float to distribution, updating the statistics fields. Args: a_float (float):
 a new value dist (:class:`endpoints_management.gen.servicecontrol_v1_messages.Distribution`):
 the Distribution being updated """

    if not dist.count:
        dist.count = 1
        dist.maximum = a_float
        dist.minimum = a_float
        dist.mean = a_float
        dist.sumOfSquaredDeviation = 0
    else:
        old_count = dist.count
        old_mean = dist.mean
        new_mean = ((old_count * old_mean) + a_float) / (old_count + 1)
        delta_sum_squares = (a_float - old_mean) * (a_float - new_mean)
        dist.count += 1
        dist.mean = new_mean
        dist.maximum = max(a_float, dist.maximum)
        dist.minimum = min(a_float, dist.minimum)
        dist.sumOfSquaredDeviation += delta_sum_squares