In a python based project, I am using this as a string:

```
f"[{a}] \
 \
<Model Merge Chain> \
[ \
  {b} \
] \
 \
UNET: \
<Model Merger (Advanced/DARE) Settings> \
\{ \
  gradient: \
  <Shell Gradient> \
  \{ \
    exterior: {c} \
    interior: {c} \
    core: {c} \
  \} \
 \
  model_mask: None \
 \
  drop_rate: 0.96 \
  ties: sum \
  rescale: off \
  seed: 42 \
  method: cosine \
  iterations: 8 \
\} \
 \
CLIP: \
<CLIP Merger (DARE) Settings> \
\{ \
  ties: sum \
  rescale: off \
  ratio: {c} \
  drop_rate: 0.96 \
  seed: 42 \
  method: gradient \
  iterations: 8 \
\} \
 \
VAE: sdxl_vae-fp16-fix"
```
The input variables are a, b and c, but I keep getting this error:
```
!!! Exception during processing!!! f-string expression part cannot include a backslash (<unknown>, line 41)
Traceback (most recent call last):
  File "D:\AI Generation\Software\ComfyUI_windows_portable\ComfyUI\execution.py", line 151, in recursive_execute
    output_data, output_ui = get_output_data(obj, input_data_all)
                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "D:\AI Generation\Software\ComfyUI_windows_portable\ComfyUI\execution.py", line 81, in get_output_data
    return_values = map_node_over_list(obj, input_data_all, obj.FUNCTION, allow_interrupt=True)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "D:\AI Generation\Software\ComfyUI_windows_portable\ComfyUI\execution.py", line 74, in map_node_over_list
    results.append(getattr(obj, func)(**slice_dict(input_data_all, i)))
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "D:\AI Generation\Software\ComfyUI_windows_portable\ComfyUI\custom_nodes\efficiency-nodes-comfyui\efficiency_nodes.py", line 4406, in evaluate
    result = simpleeval.simple_eval(python_expression, names=variables, functions=functions)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "D:\AI Generation\Software\ComfyUI_windows_portable\python_embeded\Lib\site-packages\simpleeval.py", line 748, in simple_eval
    return s.eval(expr)
           ^^^^^^^^^^^^
  File "D:\AI Generation\Software\ComfyUI_windows_portable\python_embeded\Lib\site-packages\simpleeval.py", line 428, in eval
    return self._eval(previously_parsed or self.parse(expr))
                                           ^^^^^^^^^^^^^^^^
  File "D:\AI Generation\Software\ComfyUI_windows_portable\python_embeded\Lib\site-packages\simpleeval.py", line 410, in parse
    parsed = ast.parse(expr.strip())
             ^^^^^^^^^^^^^^^^^^^^^^^
  File "ast.py", line 50, in parse
  File "<unknown>", line 41
    f"[{a}] \
 \
<Model Merge Chain> \
[ \
  {b} \
] \
 \
UNET: \
<Model Merger (Advanced/DARE) Settings> \
\{ \
  gradient: \
  <Shell Gradient> \
  \{ \
    exterior: {c} \
    interior: {c} \
    core: {c} \
  \} \
 \
  model_mask: None \
 \
  drop_rate: 0.96 \
  ties: sum \
  rescale: off \
  seed: 42 \
  method: cosine \
  iterations: 8 \
\} \
 \
CLIP: \
<CLIP Merger (DARE) Settings> \
\{ \
  ties: sum \
  rescale: off \
  ratio: {c} \
  drop_rate: 0.96 \
  seed: 42 \
  method: gradient \
  iterations: 8 \
\} \
 \
VAE: sdxl_vae-fp16-fix"


          ^
SyntaxError: f-string expression part cannot include a backslash
```

Please think about it step-by-step, to find the reasoning behind my error and possible solutions.