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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 avg(vals, count=None):
 """ Returns the average value Args: vals: List of numbers to calculate average from. count: Int of total count that vals was part of. Returns: Float average value throughout a count. """
 
    sum = 0
    for v in vals:
        sum += v
    if count is None:
        count = len(vals)
    return float(sum) / count