implement __eq__ and __hash__ for PsSymbol

src/pystencils/backend/symbols.py

@@ -45,6 +45,16 @@ class PsSymbol:
             raise PsInternalCompilerError("Symbol had no type assigned yet")
         return self._dtype
 
+    def __eq__(self, other: object) -> bool:
+        return (
+            type(self) == type(other)
+            and self._name == other._name
+            and self._dtype == other._dtype
+        )
+
+    def __hash__(self) -> int:
+        return hash((self._name, self._dtype))
+
     def __str__(self) -> str:
         dtype_str = "<untyped>" if self._dtype is None else str(self._dtype)
         return f"{self._name}: {dtype_str}"