<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _api_type(self, value):
 """ Returns the API type of the given value based on its python type. """

        if isinstance(value, six.string_types):
            return 'string'
        elif isinstance(value, six.integer_types):
            return 'integer'
        elif type(value) is datetime.datetime:
            return 'date'