docs: def getClass(self, id=None, uri=None, match=None):
          """
          get the saved-class with given ID or via other methods...
  
          Note: it tries to guess what is being passed..
  
          In [1]: g.getClass(uri='http://www.w3.org/2000/01/rdf-schema#Resource')
          Out[1]: <Class *http://www.w3.org/2000/01/rdf-schema#Resource*>
  
          In [2]: g.getClass(10)
          Out[2]: <Class *http://purl.org/ontology/bibo/AcademicArticle*>
  
          In [3]: g.getClass(match="person")
          Out[3]:
          [<Class *http://purl.org/ontology/bibo/PersonalCommunicationDocument*>,
           <Class *http://purl.org/ontology/bibo/PersonalCommunication*>,
           <Class *http://xmlns.com/foaf/0.1/Person*>]
  
          """
  
          if not id and not uri and not match:
              return None
  
          if type(id) == type("string"):
              uri = id
              id = None
              if not uri.startswith("http://"):
                  match = uri
                  uri = None
          if match:
              if type(match) != type("string"):
                  return []
              res = []
              if ":" in match: # qname
                  for x in self.classes:
                      if match.lower() in x.qname.lower():
                          res += [x]
              else:
                  for x in self.classes:
                      if match.lower() in x.uri.lower():
                          res += [x]
              return res
          else:
              for x in self.classes:
                  if id and x.id == id:
                      return x
                  if uri and x.uri.lower() == uri.lower():
                      return x
              return None