print EvalError in a slightly more user friendly way

wheel/python/clvm_rs/eval_error.py

@@ -1,4 +1,9 @@
+from .ser import sexp_to_bytes
+
 class EvalError(ValueError):
     def __init__(self, message: str, sexp):
         super().__init__(message)
         self._sexp = sexp
+
+    def __str__(self) -> str:
+        return f"({self.args[0]}, {sexp_to_bytes(self._sexp).hex()})"

wheel/python/tests/test_program.py

@@ -493,3 +493,15 @@ def test_tree_hash_no_caching(self):
         self.assertEqual(p3p._cached_sha256_treehash.hex(), eh3)
         self.assertEqual(p._cached_sha256_treehash.hex(), eh)
         self.assertEqual(p2._cached_sha256_treehash.hex(), eh2)
+
+def test_repr() -> None:
+    temp = Program.to([8, (1, "foo")])
+    assert f"{temp}" == "ff08ffff0183666f6f80"
+
+    Program.set_run_unsafe_max_cost(11000000000)
+
+    try:
+        temp.run([])
+        assert False
+    except EvalError as e:
+        assert f"{e}" == "(clvm raise, 83666f6f)"