code: def to_pandas(self):
          
          try:
              from pandas import DataFrame
          except ImportError:
              raise ImportError('You must have pandas installed to export pandas DataFrames')
  
          result = DataFrame({'from': self._mst.T[0].astype(int),
                              'to': self._mst.T[1].astype(int),
                              'distance': self._mst.T[2]})
          return result
docs: Return a Pandas dataframe of the minimum spanning tree.
  
          Each row is an edge in the tree; the columns are `from`,
          `to`, and `distance` giving the two vertices of the edge
          which are indices into the dataset, and the distance
          between those datapoints.