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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 _has_extras(ctx):
 """Determine if a MAR file has an additional section block or not. It does this by looking at where file data starts in the file. If this starts immediately after the signature data, then no additional sections are present. Args: ctx (context):
 construct parsing context Returns: True if the MAR file has an additional section block False otherwise """

    if not ctx.index.entries:
        return False

    return ctx.data_offset > 8 and ctx.data_offset > (ctx.signatures.offset_end + 8)