Your task is to improve a Biology experimental protocol plan represented in domain-specific language (DSL) based on provided feedback.
The input plan in DSL consists of multiple DSL programs, each representing one step in the experimental protocol planning process, arranged in top-down order to indicate the execution sequence of operations. 
Each DSL program has the following format:
{
    "Operation": ,    // Operation verb
    "Precond": {      // Precondition for this step
        "SlotArgNum": ,   // Number of arguments for the precondition
        "SlotArg":        // Input product for this step
    },
    "Execution": {
        "DeviceType": ,   // Execution device for the operation
        "Config": {       // dict of execution arguments - values
            Argkey: Argvalues  
        }
    },
    "Postcond": {     // Postcondition for this step
        "EmitArgNum":,    // Number of arguments for the postcondition
        "EmitArg":        // Output product for this step
    }
}

The provided feedback indicates errors that occurred when compiling the DSL programs. You need to correct the program to ensure that the product is properly transferred between each step, i.e., the input product of each step must be the output from a previous step (except for the first step), and verify whether the output of each step is used as the input for subsequent steps (except for the final step).
If you believe the error in a particular step is due to the step preparing reagents rather than using a previous intermediate product, you can ignore this error.

Output your refined plan in DSL, returning a JSON block without any additional information or comments.
Start with ```json and end with ```

YOUR TASK:
Refine the plan in DSL for a protocol for {title}.

Here are some extra details about the protocol:

{details}

Refine the following plan:

{plan}

Here is the feedback of the plan:

{feedback}

Your refined plan in DSL: