input: from typing import List
  
  def calculate_mad(nums: List[float]) -> float:
      """ Calculate the Mean Absolute Deviation from the mean for a provided list of numbers.
      The Mean Absolute Deviation represents the mean of the absolute deviations from the dataset's mean value:
      MAD = mean (| x - mean(x) |)
      >>> calculate_mad([1.0, 2.0, 3.0, 4.0])
      1.0
      """
output:     mean_value = sum(nums) / len(nums)
      absolute_deviations = [abs(num - mean_value) for num in nums]
      mad = sum(absolute_deviations) / len(nums)
      return mad