class_docstr: Volume-price trend (VPT)
  
  Is based on a running cumulative volume that adds or substracts a multiple
  of the percentage change in share price trend and current volume, depending
  upon the investment's upward or downward movements.
  
  https://en.wikipedia.org/wiki/Volume%E2%80%93price_trend
  
  Args:
      close(pandas.Series): dataset 'Close' column.
      volume(pandas.Series): dataset 'Volume' column.
      fillna(bool)=False: if True, fill nan values. DO NOT RECCOMEND to set it True.
      smoothing_factor(int)=None: will smooth default VPT implementation with SMA.
      dropnans(bool)=False: drop nans after indicator calculated.
docstr: Volume-price trend (VPT)
  
  Returns:
      pandas.Series: New feature generated.
docstr_tok: ["Volume-price","trend","(","VPT",")","Returns",":","pandas.Series",":","New","feature","generated","."]
code: def volume_price_trend(self) -> pd.Series:
      """Volume-price trend (VPT)
  
      Returns:
          pandas.Series: New feature generated.
      """
      vpt = self._check_fillna(self._vpt, value=0)
      return pd.Series(vpt, name="vpt")
  
imports: import typing
  import numpy
  import pandas
  from ta.utils import IndicatorMixin, _ema
label_desc: Use image node_id 3 for calling the VolumePriceTrendIndicator obj's underlying member method code with example usage: obj.volume_price_trend() and returns: pd