code: def get_values(self, k, v):
      
      metadata = self.metadata
      values = []
      if metadata != None:
        if k in metadata:
          for metav in metadata[k]:
            if v in metav:
              values.append(metav[v])
      return values
docs: Get a list of values from the key value metadata attribute.
      
      Args:
        k (str):
          Key in :class:`api.results`.metadata
        v (str):
          Values from each item in the key of :class:`api.results`.metadata
      
      Returns:
        A list containing all the ``v`` values in the ``k`` key for the  :class:`api.results`.metadata attribute.