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Unipolar graphs are interval filaments graphs. Brief sketch: If $G$ is unipolar there are vertex sets $A$ and $B$ s.th. $A$ induces a clique and $B$ induces a set of cliques with vertex sets $B_1, \dotsc, B_k$, say. Create a filament for each vertex of $G$ attached to the $x$-axis grouping them in order $B_1, \dotsc, B_k, A$. We can entangle the filaments in each group to create the cliques $A, B_1, \dotsc, B_k$ in $G$. Any edge between $A$ and $B_k$ can then be created by having the filaments of their endpoints intersect close to the boundary between $B_k$ and $A$. We place the intersections above all earlier intersections to avoid prohibited intersections. Once $B_k$ is done, we continue with edges between $B_{k-1}$ and $A$. And so on.