def _stringify_value(self, value):
        """
        This method stringifies values of environment variables. If the value of the method is a list or dictionary,
        then this method will replace it with empty string. Values of environment variables in Lambda must be a string.
        List or dictionary usually means they are intrinsic functions which have not been resolved.

        :param value: Value to stringify
        :return string: Stringified value
        """

        # List/dict/None values are replaced with a blank
        if isinstance(value, (dict, list, tuple)) or value is None:
            result = self._BLANK_VALUE

        # str(True) will output "True". To maintain backwards compatibility we need to output "true" or "false"
        elif value is True:
            result = "true"
        elif value is False:
            result = "false"

        # value is a scalar type like int, str which can be stringified
        # do not stringify unicode in Py2, Py3 str supports unicode
        elif sys.version_info.major > 2:
            result = str(value)
        elif not isinstance(value, unicode):  # noqa: F821 pylint: disable=undefined-variable
            result = str(value)
        else:
            result = value

        return result
This method stringifies values of environment variables. If the value of the method is a list or dictionary,
        then this method will replace it with empty string. Values of environment variables in Lambda must be a string.
        List or dictionary usually means they are intrinsic functions which have not been resolved.

        :param value: Value to stringify
        :return string: Stringified value