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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 _read_content_or_path(content_or_path):
 """ If `content_or_path` contains ``\\n``, return it. Else assume, that it is path and read file at that path. Args: content_or_path (str):
 Content or path to the file. Returns: str: Content. Raises: IOError: whhen the file is not found. """

    if "\n" in content_or_path.strip():
        return content_or_path

    if not os.path.exists(content_or_path):
        raise IOError("File '%s' doesn't exists!" % content_or_path)

    with open(content_or_path) as f:
        return f.read()