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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 _related(self, concept):
 """ Returns related concepts for a concept. """

        return concept.hypernyms() + \
                concept.hyponyms() + \
                concept.member_meronyms() + \
                concept.substance_meronyms() + \
                concept.part_meronyms() + \
                concept.member_holonyms() + \
                concept.substance_holonyms() + \
                concept.part_holonyms() + \
                concept.attributes() + \
                concept.also_sees() + \
                concept.similar_tos()