mypy?

qgym/envs/routing/routing_state.py

@@ -89,7 +89,7 @@ def __init__(  # pylint: disable=too-many-arguments
         """An array of 2-tuples of integers, where every tuple represents a, not
         specified, gate acting on the two qubits labeled by the integers in the tuples.
         """
-        self.mapping = np.arange(self.n_qubits)
+        self.mapping = np.arange(self.n_qubits, dtype=np.int_)
         """Array of which each index represents a logical qubit and each value
         represents a physical qubit.
         """