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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 _callable_contents(obj):
 """Return the signature contents of a callable Python object. """

    try:
        # Test if obj is a method.
        return _function_contents(obj.__func__)

    except AttributeError:
        try:
            # Test if obj is a callable object.
            return _function_contents(obj.__call__.__func__)

        except AttributeError:
            try:
                # Test if obj is a code object.
                return _code_contents(obj)

            except AttributeError:
                # Test if obj is a function object.
                return _function_contents(obj)