'Returns all the tenants under a parent tenant.
:param uri: The parent tenant name
:returns: JSON payload of tenant list'

def tenant_list(self, uri=None):

    if (not uri):
        uri = self.tenant_getid()
    tenantdtls = self.tenant_show_by_uri(uri)
    if (tenantdtls and (not (('parent_tenant' in tenantdtls) and ('id' in tenantdtls['parent_tenant'])))):
        (s, h) = common.service_json_request(self.ipaddr, self.port, 'GET', self.URI_TENANTS_SUBTENANT.format(uri), None)
        o = common.json_decode(s)
        return o['subtenant']
    else:
        return []
