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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 nextConcept(self, concepturi):
 """Returns the next skos concept in the list of concepts. If it's the last one, returns the first one."""

        if concepturi == self.skosConcepts[-1].uri:
            return self.skosConcepts[0]
        flag = False
        for x in self.skosConcepts:
            if flag == True:
                return x
            if x.uri == concepturi:
                flag = True
        return None