Exception message: Build graph construction failed: ExecutionError Received unexpected Throw state(s):
Computing Select(DescendantAddresses(directory='src/python'), =TransitiveHydratedTargets)
  Computing Task(<function transitive_hydrated_targets at 0x10dfd2a28>, DescendantAddresses(directory='src/python'), =TransitiveHydratedTargets)
    Computing Task(<function hydrate_target at 0x10dfd2b18>, 3rdparty/python:leveldb:util, =HydratedTarget)
      Computing Task(<function hydrate_struct at 0x10dc7dc08>, 3rdparty/python:leveldb:util, =(symbol table types))
        Computing Task(<function resolve_unhydrated_struct at 0x10dc7dc80>, 3rdparty/python:leveldb:util, =UnhydratedStruct)
          Computing Task(<function parse_address_family at 0x10dc7d398>, Dir(path='3rdparty/python:leveldb'), =AddressFamily)
            Throw(Directory "Dir(path='3rdparty/python:leveldb')" does not contain build files.)
              Traceback (most recent call last):
                File "/Users/benjyw/.cache/pants/setup/bootstrap-Darwin-x86_64/1.5.0rc1/lib/python2.7/site-packages/pants/engine/native.py", line 323, in call
                  val = func(*args)
                File "/Users/benjyw/.cache/pants/setup/bootstrap-Darwin-x86_64/1.5.0rc1/lib/python2.7/site-packages/pants/engine/build_files.py", line 75, in parse_address_family
                  raise ResolveError('Directory "{}" does not contain build files.'.format(path))
              ResolveError: Directory "Dir(path='3rdparty/python:leveldb')" does not contain build files.