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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_from(value):
 """Read file and return contents."""

    path = normalized_path(value)
    if not os.path.exists(path):
        raise argparse.ArgumentTypeError("%s is not a valid path." % path)
    LOG.debug("%s exists.", path)
    with open(path, 'r') as reader:
        read = reader.read()
    return read