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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 median(arr):
 """median of the values, must have more than 0 entries. :param arr: list of numbers :type arr: number[] a number array :return: median :rtype: float """

  if len(arr) == 0:
    sys.stderr.write("ERROR: no content in array to take average\n")
    sys.exit()
  if len(arr) == 1: return arr[0]
  quot = len(arr)/2
  rem = len(arr)%2
  if rem != 0:
    return sorted(arr)[quot]
  return float(sum(sorted(arr)[quot-1:quot+1]))/float(2)