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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_self_uri(self, content_type):
        "return the first self uri with the content_type"
        try:
            return [self_uri for self_uri in self.self_uri_list
                    if self_uri.content_type == content_type][0]
        except IndexError:
            return None