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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_definition(self, stmt: Statement, sctx: SchemaContext) -> Tuple[Statement, SchemaContext]: """Find the statement defining a grouping or derived type. Args: stmt: YANG "uses" or "type" statement. sctx: Schema context where the definition is used. Returns: A tuple consisting of the definition statement ('grouping' or 'typedef') and schema context of the definition. Raises: ValueError: If `stmt` is neither "uses" nor "type" statement. ModuleNotRegistered: If `mid` is not registered in the data model. UnknownPrefix: If the prefix specified in the argument of `stmt` is not declared. DefinitionNotFound: If the corresponding definition is not found. """

        if stmt.keyword == "uses":
            kw = "grouping"
        elif stmt.keyword == "type":
            kw = "typedef"
        else:
            raise ValueError("not a 'uses' or 'type' statement")
        loc, did = self.resolve_pname(stmt.argument, sctx.text_mid)
        if did == sctx.text_mid:
            dstmt = stmt.get_definition(loc, kw)
            if dstmt:
                return (dstmt, sctx)
        else:
            dstmt = self.modules[did].statement.find1(kw, loc)
            if dstmt:
                return (dstmt, SchemaContext(sctx.schema_data, sctx.default_ns, did))
        for sid in self.modules[did].submodules:
            dstmt = self.modules[sid].statement.find1(kw, loc)
            if dstmt:
                return (
                    dstmt, SchemaContext(sctx.schema_data, sctx.default_ns, sid))
        raise DefinitionNotFound(kw, stmt.argument)