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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 ast_from_module(self, module, modname=None):
 """given an imported module, return the astroid object"""

        modname = modname or module.__name__
        if modname in self.astroid_cache:
            return self.astroid_cache[modname]
        try:
            # some builtin modules don't have __file__ attribute
            filepath = module.__file__
            if modutils.is_python_source(filepath):
                return self.ast_from_file(filepath, modname)
        except AttributeError:
            pass
        from astroid.builder import AstroidBuilder

        return AstroidBuilder(self).module_build(module, modname)