code: def get_fscore(self, fmap=''):
          
          trees = self.get_dump(fmap)
          fmap = {}
          for tree in trees:
              for line in tree.split('\n'):
                  arr = line.split('[')
                  if len(arr) == 1:
                      continue
                  fid = arr[1].split(']')[0]
                  fid = fid.split('<')[0]
                  if fid not in fmap:
                      fmap[fid] = 1
                  else:
                      fmap[fid] += 1
          return fmap
docs: Get feature importance of each feature.
  
          Parameters
          ----------
          fmap: str (optional)
             The name of feature map file