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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 copy(app, need, needs, option, need_id=None):
 """ Copies the value of one need option to another .. code-block:: jinja .. req:: copy-example :id: copy_1 :tags: tag_1, tag_2, tag_3 :status: open .. spec:: copy-example implementation :id: copy_2 :status: [[copy("status", "copy_1")]] :links: copy_1 :comment: [[copy("id")]] Copies status of ``copy_1`` to own status. Sets also a comment, which copies the id of own need. .. test:: test of specification and requirement :id: copy_3 :links: copy_2; [[copy('links', 'copy_2')]] :tags: [[copy('tags', 'copy_1')]] Set own link to ``copy_2`` and also copies all links from it. Also copies all tags from copy_1. .. req:: copy-example :id: copy_1 :tags: tag_1, tag_2, tag_3 :status: open .. spec:: copy-example implementation :id: copy_2 :status: [[copy("status", "copy_1")]] :links: copy_1 :comment: [[copy("id")]] Copies status of ``copy_1`` to own status. Sets also a comment, which copies the id of own need. .. test:: test of specification and requirement :id: copy_3 :links: copy_2; [[copy('links', 'copy_2')]] :tags: [[copy('tags', 'copy_1')]] Set own link to ``copy_2`` and also copies all links from it. Also copies all tags from copy_1. :param option: Name of the option to copy :param need_id: id of the need, which contains the source option. If None, current need is taken :return: string of copied need option """

    if need_id is not None:
        need = needs[need_id]

    return need[option]