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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 clear_caches():
 # suppress(unused-function) """Clear all caches."""

    for _, reader in _spellchecker_cache.values():
        reader.close()

    _spellchecker_cache.clear()
    _valid_words_cache.clear()
    _user_dictionary_cache.clear()