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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_instance_variables(node, bound_name_classifier=BOUND_METHOD_ARGUMENT_NAME):
 """ Return instance variables used in an AST node """

    node_attributes = [
        child
        for child in ast.walk(node)
        if isinstance(child, ast.Attribute) and
        get_attribute_name_id(child) == bound_name_classifier
    ]
    node_function_call_names = [
        get_object_name(child)
        for child in ast.walk(node)
        if isinstance(child, ast.Call)
    ]
    node_instance_variables = [
        attribute
        for attribute in node_attributes
        if get_object_name(attribute) not in node_function_call_names
    ]
    return node_instance_variables