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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_help_for_estimator(prefix, estimator, defaults=None):
 """Yield help lines for the given estimator and prefix."""

    from numpydoc.docscrape import ClassDoc

    defaults = defaults or {}
    estimator = _extract_estimator_cls(estimator)
    yield "<{}> options:".format(estimator.__name__)

    doc = ClassDoc(estimator)
    yield from _get_help_for_params(
        doc['Parameters'],
        prefix=prefix,
        defaults=defaults,
    )
    yield ''