':return:
A list of zero or more unicode strings of the OCSP URLs for this
cert'

@property
def ocsp_urls(self):

    if (not self.authority_information_access_value):
        return []
    output = []
    for entry in self.authority_information_access_value:
        if (entry[u'access_method'].native == u'ocsp'):
            location = entry[u'access_location']
            if (location.name != u'uniform_resource_identifier'):
                continue
            url = location.native
            if (url.lower()[0:7] == u'http://'):
                output.append(url)
    return output
