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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 _merge_last(values, merge_after, merge_with=' '):
    '''
    Merge values all values after X into the last value
    '''
    if len(values) > merge_after:
        values = values[0:(merge_after-1)] + [merge_with.join(values[(merge_after-1):])]

    return values