CRA_Assembly.add_block_block_interfaces
- CRA_Assembly.add_block_block_interfaces(a, b, interfaces)
 Add an interface between two blocks.
- Parameters:
 - a
compas_assembly.datastructures.Block The “from” block.
- b
compas_assembly.datastructures.Block The “to” block.
- interfacesList[
compas_assembly.datastructures.Interface] The interface.
- a
 - Returns:
 - tuple[hashable, hashable]
 the identifier of the edge in the graph corresponding to the interface.
- Raises:
 - AssemblyError
 If at least one of the blocks is not part of the assembly.