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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 contains_variables_from_set(expression, variables):
 """Returns True iff the expression contains any of the variables from the given set."""

    if hasattr(expression, 'variable_name') and expression.variable_name in variables:
        return True
    if isinstance(expression, Operation):
        return any(contains_variables_from_set(o, variables) for o in op_iter(expression))
    return False