Check if node at given JPath within given data structure does exist.

    :param str structure: data structure to be searched
    :param str jpath: JPath to be evaluated
    :return: True or False
    :rtype: bool

def jpath_exists(structure, jpath):
    """
    Check if node at given JPath within given data structure does exist.

    :param str structure: data structure to be searched
    :param str jpath: JPath to be evaluated
    :return: True or False
    :rtype: bool
    """
    result = jpath_value(structure, jpath)
    if not result is None:
        return True
    return False