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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def read(file_or_stream, fmt, as_version=4, **kwargs):
 """Read a notebook from a file"""

    fmt = long_form_one_format(fmt)
    if fmt['extension'] == '.ipynb':
        notebook = nbformat.read(file_or_stream, as_version, **kwargs)
        rearrange_jupytext_metadata(notebook.metadata)
        return notebook

    return reads(file_or_stream.read(), fmt, **kwargs)