code: def validatefeatures(self,features):
          
          validatedfeatures = []
          for feature in features:
              if isinstance(feature, int) or isinstance(feature, float):
                  validatedfeatures.append( str(feature) )
              elif self.delimiter in feature and not self.sklearn:
                  raise ValueError("Feature contains delimiter: " + feature)
              elif self.sklearn and isinstance(feature, str): #then is sparse added together
                  validatedfeatures.append(feature)
              else:
                  validatedfeatures.append(feature)
          return validatedfeatures
docs: Returns features in validated form, or raises an Exception. Mostly for internal use