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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 MFI(frame, n=14, high_col='high', low_col='low', close_col='close', vol_col='Volume'):
 """money flow inedx"""

    return _frame_to_series(frame, [high_col, low_col, close_col, vol_col], talib.MFI, n)