class_docstr: Money Flow Index (MFI)
  
  Uses both price and volume to measure buying and selling pressure. It is
  positive when the typical price rises (buying pressure) and negative when
  the typical price declines (selling pressure). A ratio of positive and
  negative money flow is then plugged into an RSI formula to create an
  oscillator that moves between zero and one hundred.
  
  http://stockcharts.com/school/doku.php?id=chart_school:technical_indicators:money_flow_index_mfi
  
  Args:
      high(pandas.Series): dataset 'High' column.
      low(pandas.Series): dataset 'Low' column.
      close(pandas.Series): dataset 'Close' column.
      volume(pandas.Series): dataset 'Volume' column.
      window(int): n period.
      fillna(bool): if True, fill nan values.
code: def _run(self):
      typical_price = (self._high + self._low + self._close) / 3.0
      up_down = np.where(
          typical_price > typical_price.shift(1),
          1,
          np.where(typical_price < typical_price.shift(1), -1, 0),
      )
      mfr = typical_price * self._volume * up_down
  
      # Positive and negative money flow with n periods
      min_periods = 0 if self._fillna else self._window
      n_positive_mf = mfr.rolling(
          self._window, min_periods=min_periods
      ).apply(lambda x: np.sum(np.where(x >= 0.0, x, 0.0)), raw=True)
      n_negative_mf = abs(
          mfr.rolling(self._window, min_periods=min_periods).apply(
              lambda x: np.sum(np.where(x < 0.0, x, 0.0)), raw=True
          )
      )
  
      # n_positive_mf = np.where(mf.rolling(self._window).sum() >= 0.0, mf, 0.0)
      # n_negative_mf = abs(np.where(mf.rolling(self._window).sum() < 0.0, mf, 0.0))
  
      # Money flow index
      mfi = n_positive_mf / n_negative_mf
      self._mfi = 100 - (100 / (1 + mfi))
  
imports: import typing
  import numpy
  import pandas
  from ta.utils import IndicatorMixin, _ema
label_desc: Use image node_id 2 for calling the MFIIndicator obj's underlying member method code with example usage: obj._run() without return types