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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 is_valid_chunksize(chunk_size):
 """Check if size is valid."""

        min_csize = current_app.config['FILES_REST_MULTIPART_CHUNKSIZE_MIN']
        max_csize = current_app.config['FILES_REST_MULTIPART_CHUNKSIZE_MAX']
        return chunk_size >= min_csize and chunk_size <= max_csize