code: def reset(self, collection, jsonFieldInit = None) :
          if not jsonFieldInit:
              jsonFieldInit = {}
          
          self.collection = collection
          self.connection = self.collection.connection
          self.documentsURL = self.collection.documentsURL
  
  
          self.URL = None
          self.setPrivates(jsonFieldInit)
          self._store = DocumentStore(self.collection, validators=self.collection._fields, initDct=jsonFieldInit)
          if self.collection._validation['on_load']:
              self.validate()
  
          self.modified = True
docs: replaces the current values in the document by those in jsonFieldInit