Small fix to client.view_api() in the case of default file values

[abidlabs]

I forgot to address this comment by @freddyaboulton: #7732 (comment). This PR fixes it.

Test with:

import gradio as gr

demo = gr.Interface(
    lambda x,y:x,
    [gr.Audio("test.mp3"), gr.Number()],
    "audio"
)

_, url, _ = demo.launch(inline=False)

from gradio_client import Client

client = Client(url)

client.view_api()

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---

Install Gradio from this PR

pip install https://gradio-builds.s3.amazonaws.com/04fd29dbaa36e9f59de5e8ae34cfd103c548b998/gradio-4.22.0-py3-none-any.whl

Install Gradio Python Client from this PR

pip install "gradio-client @ git+https://github.com/gradio-app/gradio@04fd29dbaa36e9f59de5e8ae34cfd103c548b998#subdirectory=client/python"

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This Pull Request includes changes to the following packages.

Package	Version
gradio	patch
gradio_client	patch

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Small fix to client.view_api() in the case of default file values

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[aliabd]

Nice! works great for me. Shows:

Client.predict() Usage Info
---------------------------
Named API endpoints: 1

 - predict(x, y, api_name="/predict") -> output
    Parameters:
     - [Audio] x: filepath (not required, defaults to:   file("http://127.0.0.1:7860/file=/Users/aliabdalla/Documents/dev/gradio/client/python/test.mp3"))
     - [Number] y: float (required)
    Returns:
     - [Audio] output: filepath

[abidlabs]

Thanks @aliabd!