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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 code_block(text, language=""):
 """Return a code block. If a language is specified a fenced code block is produced, otherwise the block is indented by four spaces. Keyword arguments: language -- Specifies the language to fence the code in (default blank). ' This is a simple codeblock.' ' This is a simple codeblock.\\n But it has a linebreak!' '```python\\nThis block of code has a specified language.\\n```' '```python\\nSo\\nmany\\nlinebreaks.\\n```' """

    if language:
        return "```" + language + "\n" + text + "\n```"
    return "\n".join(["    " + item for item in text.split("\n")])