Format account balance as hex string

mythril/analysis/solver.py

@@ -133,7 +133,7 @@ def _get_concrete_state(initial_accounts: Dict, min_price_dict: Dict[str, int]):
         data["nonce"] = account.nonce
         data["code"] = account.code.bytecode
         data["storage"] = str(account.storage)
-        data["balance"] = min_price_dict.get(address, 0)
+        data["balance"] = hex(min_price_dict.get(address, 0))
         accounts[hex(address)] = data
     return {"accounts": accounts}