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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 get_files(files, extnames=['.root']):
 """Extract a list of file paths from a list containing both paths and file lists with one path per line."""


    files_out = []
    for f in files:

        mime = mimetypes.guess_type(f)
        if os.path.splitext(f)[1] in extnames:
            files_out += [f]
        elif mime[0] == 'text/plain':
            files_out += list(np.loadtxt(f, unpack=True, dtype='str'))
        else:
            raise Exception('Unrecognized input type.')

    return files_out