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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 base_path(self):
 """ Calculate the APIs base path """

        path = UrlPath()

        # Walk up the API to find the base object
        parent = self.parent
        while parent:
            path_prefix = getattr(parent, 'path_prefix', NoPath)
            path = path_prefix + path
            parent = getattr(parent, 'parent', None)

        return path