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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 make_unique_name(base, existing=[], format="%s_%s"):
 """ Return a name, unique within a context, based on the specified name. @param base: the desired base name of the generated unique name. @param existing: a sequence of the existing names to avoid returning. @param format: a formatting specification for how the name is made unique. """

    count = 2
    name = base
    while name in existing:
        name = format % (base, count)
        count += 1

    return name