docs: def load(self, schemafile=None):
          """Load and process the schema file"""
          if schemafile is not None:
              self._schemafile = schemafile
  
          try:
              self.data = json.load(open(self._schemafile))
          except (IOError, ValueError), e:
              msg = "Could not load schema file '" + self._schemafile + "': '" + str(e) + "'"
              raise jsonschema.SchemaError(msg)
  
          self.loaded = True