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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 string_build(self, data, modname="", path=None):
 """Build astroid from source code string."""

        module = self._data_build(data, modname, path)
        module.file_bytes = data.encode("utf-8")
        return self._post_build(module, "utf-8")