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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 _locate_element(dom, el_content, transformer=None):
 """ Find element containing `el_content` in `dom`. Use `transformer` function to content of all elements in `dom` in order to correctly transforming them to match them with `el_content`. Args: dom (obj):
 HTMLElement tree. el_content (str):
 Content of element will be picked from `dom`. transformer (fn, default None):
 Transforming function. Note: `transformer` parameter can be for example simple lambda:: lambda x: x.strip() Returns: list: Matching HTMLElements. """

    return dom.find(
        None,
        fn=utils.content_matchs(el_content, transformer)
    )