'Creates a definition object for one of the types in the chain.
The definition will be built from the given name and type and will
use the properties specified in the chain\'s resource_properties
property. All types in the chain are given the same set of properties.
:type resource_name: str
:type resource_type: str
:param depends_on: if specified, the new resource will depend on the
resource name specified
:type depends_on: str
:return: resource definition suitable for adding to a template
:rtype: heat.engine.rsrc_defn.ResourceDefinition'

def _build_resource_definition(self, resource_name, resource_type, depends_on=None):

    properties = self.properties[self.RESOURCE_PROPERTIES]
    return rsrc_defn.ResourceDefinition(resource_name, resource_type, properties, depends=depends_on)
