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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 is_end_node(node):
 """Checks if a node is the "end" keyword. Args: node: AST node. Returns: True if the node is the "end" keyword, otherwise False. """

    return (isinstance(node, ast.Expr) and
            isinstance(node.value, ast.Name) and
            node.value.id == 'end')