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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_all_formatters():
 """Return a generator for all formatter classes."""

    # NB: this returns formatter classes, not info like get_all_lexers().
    for info in itervalues(FORMATTERS):
        if info[1] not in _formatter_cache:
            _load_formatters(info[0])
        yield _formatter_cache[info[1]]
    for _, formatter in find_plugin_formatters():
        yield formatter