code: def parse_parameters(cls, parameters, possible_fields=None):
          
          if possible_fields is not None:
              # make sure field names are strings and not unicode
              possible_fields = dict([[f, dt]
                  for f,dt in possible_fields.items()])
              class ModifiedArray(cls):
                  _staticfields = possible_fields
              cls = ModifiedArray
          return cls(1, names=parameters).fieldnames
docs: Parses a list of parameters to get the list of fields needed in
          order to evaluate those parameters.
  
          Parameters
          ----------
          parameters : (list of) strings
              The list of desired parameters. These can be (functions of) fields
              or virtual fields.
          possible_fields : {None, dict}
              Specify the list of possible fields. Must be a dictionary given
              the names, and dtype of each possible field. If None, will use this
              class's `_staticfields`.
  
          Returns
          -------
          list :
              The list of names of the fields that are needed in order to
              evaluate the given parameters.