<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def defaultset(self, annotationtype):
 """Obtain the default set for the specified annotation type. Arguments: annotationtype: The type of annotation, this is conveyed by passing the corresponding annototion class (such as :class:`PosAnnotation` for example), or a member of :class:`AnnotationType`, such as ``AnnotationType.POS``. Returns: the set (str) Raises: :class:`NoDefaultError` if the annotation type does not exist or if there is ambiguity (multiple sets for the same type) """


        if inspect.isclass(annotationtype) or isinstance(annotationtype,AbstractElement): annotationtype = annotationtype.ANNOTATIONTYPE
        try:
            return list(self.annotationdefaults[annotationtype].keys())[0]
        except KeyError:
            raise NoDefaultError
        except IndexError:
            raise NoDefaultError