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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_purrlog(path):
 """Checks if path refers to a valid purrlog. Path must exist, and must contain either at least one directory called entry-YYYYMMDD-HHMMSS, or the file "dirconfig" """

        if not os.path.isdir(path):
            return False
        if list(filter(os.path.isdir, glob.glob(
                os.path.join(path, "entry-[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]-[0-9][0-9][0-9][0-9][0-9][0-9]")))):
            return True
        return os.path.exists(os.path.join(path, "dirconfig"))