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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 calculate_up_moves(high_data):
 """ Up Move. Formula: UPMOVE = Ht - Ht-1 """

    up_moves = [high_data[idx] - high_data[idx-1] for idx in range(1, len(high_data))]
    return [np.nan] + up_moves