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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 replace_lines(regexer, handler, lines):
 """Uses replacement handler to perform replacements on lines of text First we strip off all whitespace We run the replacement on a clean 'content' string Finally we replace the original content with the replaced version This ensures that we retain the correct whitespace from the original line """

    result = []
    for line in lines:
        content = line.strip()
        replaced = regexer.sub(handler, content)
        result.append(line.replace(content, replaced, 1))
    return result