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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 _make_definition(self, definition):
 """ Generate a definition. The input might already be a `EndpointDefinition` or it might be a tuple. """

        if not definition:
            return EndpointDefinition()
        if isinstance(definition, EndpointDefinition):
            return definition
        elif len(definition) == 1:
            return EndpointDefinition(
                func=definition[0],
            )
        elif len(definition) == 2:
            return EndpointDefinition(
                func=definition[0],
                response_schema=definition[1],
            )
        elif len(definition) == 3:
            return EndpointDefinition(
                func=definition[0],
                request_schema=definition[1],
                response_schema=definition[2],
            )
        elif len(definition) == 4:
            return EndpointDefinition(
                func=definition[0],
                request_schema=definition[1],
                response_schema=definition[2],
                header_func=definition[3],
            )