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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 load_data(self, filename, ext):
 """Load data from filename"""

        from spyder_kernels.utils.iofuncs import iofunctions
        from spyder_kernels.utils.misc import fix_reference_name

        glbs = self._mglobals()

        load_func = iofunctions.load_funcs[ext]
        data, error_message = load_func(filename)

        if error_message:
            return error_message

        for key in list(data.keys()):
            new_key = fix_reference_name(key, blacklist=list(glbs.keys()))
            if new_key != key:
                data[new_key] = data.pop(key)

        try:
            glbs.update(data)
        except Exception as error:
            return str(error)

        return None