\begin{table}
\centering
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Hello &  &  & World &  \\
& Foo &  &  & Bar \\
Sepal.Length & Sepal.Width & Petal.Length & Petal.Width & Species \\
5.1 & 3.5 & 1.4 & 0.2 & setosa \\
4.9 & 3.0 & 1.4 & 0.2 & setosa \\
4.7 & 3.2 & 1.3 & 0.2 & setosa \\
4.6 & 3.1 & 1.5 & 0.2 & setosa \\
5.0 & 3.6 & 1.4 & 0.2 & setosa \\
5.4 & 3.9 & 1.7 & 0.4 & setosa \\
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