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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 shrink_file(in_filepath, api_key=None, out_filepath=None):
 """Shrink png file and write it back to a new file The default file path replaces ".png" with ".tiny.png". returns api_info (including info['ouput']['filepath']) """

    info = get_shrink_file_info(in_filepath, api_key, out_filepath)
    write_shrunk_file(info)
    return info