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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 stream_files(files, chunk_size=default_chunk_size):
 """Gets a buffered generator for streaming files. Returns a buffered generator which encodes a file or list of files as :mimetype:`multipart/form-data` with the corresponding headers. Parameters files : str The file(s) to stream chunk_size : int Maximum size of each stream chunk """

    stream = FileStream(files, chunk_size=chunk_size)

    return stream.body(), stream.headers