from .snapshot import BaseSnapshot, SnapshotFactory, SnapshotDescriptor
from .trajectory import Trajectory

from .topology import Topology

from . import features

from .dynamics_engine import (
    DynamicsEngine, NoEngine, EngineError,
    EngineNaNError, EngineMaxLengthError)

from .external_engine import ExternalEngine

from . import external_snapshots

from . import gromacs

@@ -131,16 +131,32 @@
 Topology
+, MDTrajTopology
 %0A%0Afrom .

allow import from paths.engines