s class="source">
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<span>Expand source code</span>
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<pre><code class="python">from .baseinternal import BaseInternal


class Jacket(BaseInternal):
    def __init__(self, thickness=5, startYFraction=0.5):
        self.thickness = thickness
        self.startYFraction = startYFraction
        return

    def draw(self, ctx):
        if self.parent is None:
            Warning(&#34;Internal has no parent set!&#34;)
            return

        unit = self.parent

        if unit.capLength == 