code: def data(self, **kwargs):
          
  
          key = kwargs.pop('key', None)
          value = kwargs.pop('value', None)
          dictionary = kwargs.pop('dictionary', None)
  
          # Fail if a key and a dictionary or a value and a dictionary are given
          if (key is not None and dictionary is not None) or \
             (value is not None and dictionary is not None):
              raise ValueError
  
          # If only a key was provided return the corresponding value
          if key is not None and value is None:
              return self._get_content(key)
  
          # if a key and a value are passed in
          if key is not None and value is not None:
              self._set_content(key, value)
  
          if dictionary is not None:
              for key in dictionary.keys():
                  value = dictionary[key]
                  self._set_content(key, value)
  
          return self._get_content()
docs: If a key is passed in, a corresponding value will be returned.
          If a key-value pair is passed in then the corresponding key in
          the database will be set to the specified value.
          A dictionary can be passed in as well.
          If a key does not exist and a value is provided then an entry
          will be created in the database.