add TensorDotOperator

src/__init__.py

@@ -46,6 +46,7 @@ from .operators.simple_linear_operators import (
     VdotOperator, ConjugationOperator, Realizer, FieldAdapter, ducktape,
     GeometryRemover, NullOperator, PartialExtractor, Imaginizer)
 from .operators.matrix_product_operator import MatrixProductOperator
+from .operators.tensor_dot_operator import TensorDotOperator
 from .operators.value_inserter import ValueInserter
 from .operators.energy_operators import (
     EnergyOperator, GaussianEnergy, PoissonianEnergy, InverseGammaEnergy,