> ## Documentation Index
> Fetch the complete documentation index at: https://docs.inferless.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Input / Output Schema

This doc helps you configure the input / outputs of the 'infer' function in the InferlessPythonModule class. This is the interface for inputs between the model and the Inferless platform.

You have to define the **input\_schema.py** in your GitHub/GitLab repository this will help us create the Input parameters :

For each input, there are 3 fields required and 1 optional field

* **datatype**: "STRING", "BOOL", "INT8", "INT16", "INT32", "FP16" "FP32", "UINT8", "UINT16", "UINT32", "UINT64", "INT64" , "FP64" , "BYTES", "BF16"

* **shape**: The length of the array, If the shape is \[1] you will get the variable, if the array > 1 you will get an array, If the length is variable you can put -1

* **required**: If the parameter is required in all API calls

* **example**( optional ): Sample value for calling the API

In code

```app.py Example theme={null}
def infer(self, inputs):
    prompt = inputs["prompt"] # "There is a fine house in the forest"
    shape = inputs["shape"] # [ 512,1 ]
```

In input\_schema.py

```input_schema Example theme={null}
INPUT_SCHEMA = {
    "prompt": {
        'datatype': 'STRING',
        'required': True,
        'shape': [1],
        'example': ["There is a fine house in the forest"]
    },
    'shape': {
        'datatype': 'INT8',
        'required': False,
        'example': [ 512, 1 ],
        'shape': [2]
    },
}
```

### Variable Length Inputs

For inputs that can take a variable number of values, you can set the `shape` fields to `[-1]`. This indicates that the length of the array is not fixed and can vary.

Here's an example:

```python theme={null}
INPUT_SCHEMA = {
    "variable_input": {
        'datatype': 'STRING',
        'required': True,
        'shape': [-1],
        'example': ["value1", "value2", "value3"]
    },
}# Variable Length Inputs
```

## Outputs

You can return any dictionary in the return statement of app.py. You don't need to provide any configuration.

### Returning Dicts

```python theme={null}
# Example Return Statement 

return { "label_1" : 0.398 , "label_2" : 0.563, "label_3" : 0.434 }
```

### Returning Variable Length Array

```
# Example Return Statement 
return { "generated_images_base64" : [ img_str1 , img_str2 , img_str3 ] }
```

### Returning Dictionary with Variable keys

```
# Example Return Statement 
dict = {"label_x": 0.4554 , "label_y", 0.3232 }
return { "result": json.dumps(dict) }
```