Surjective arrows - LaTeX symbols

Symbol Command
$\twoheadrightarrow$ \twoheadrightarrow
$\twoheadleftarrow$ \twoheadleftarrow
$\xtwoheadrightarrow{function}$ \xtwoheadrightarrow{function}
$\xtwoheadleftarrow{function}$ \xtwoheadleftarrow{function}

LaTeX arrow

LaTeX