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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 _notify_reader_writes(writeto):
 """Notify reader closures about these writes and return a sorted list of thus-satisfied closures. """

    satisfied = []
    for var in writeto:
        if var.readable:
            for reader in var.readers:
                reader.notify_read_ready()
                if reader.satisfied:
                    satisfied.append(reader)
    return Closure.sort(satisfied)