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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(name, existing_names, name_format="{name}_{index}", start=2):
 """Return a unique name based on `name_format` and `name`."""

    index = start
    new_name = name
    while new_name in existing_names:
        new_name = name_format.format(name=name, index=index)
        index += 1

    return new_name