@staticmethod
def convert_duration(duration):
    """
        Converts the given duration (float value in seconds) into a STRING
        value needed by the backend system (TeamCity uses milliseconds, for
        example)
        :param duration: Something that can be converted by float()
        :return: A string
        """
    if duration is not None:
        return '{:.4f}'.format(float(duration))
    else:
        return ''
