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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 check_postconditions(f, return_value):
 """ Runs all of the postconditions. """

    f = getattr(f, 'wrapped_fn', f)
    if f and hasattr(f, 'postconditions'):
        for cond in f.postconditions:
            cond(return_value)