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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 find(basedir, string):
 """ walk basedir and return all files matching string """

    matches = []
    for root, dirnames, filenames in os.walk(basedir):
        for filename in fnmatch.filter(filenames, string):
            matches.append(os.path.join(root, filename))
    return matches