def _get_anchor_data(anchor_data, glyphSet, components, anchor_name):
    """Get data for an anchor from a list of components."""

    anchors = []
    for component in components:
        for anchor in glyphSet[component.baseGlyph].anchors:
            if anchor.name == anchor_name:
                anchors.append((anchor, component))
                break
    if len(anchors) > 1:
        for i, (anchor, component) in enumerate(anchors):
            t = Transform(*component.transformation)
            name = '%s_%d' % (anchor.name, i + 1)
            anchor_data[name] = t.transformPoint((anchor.x, anchor.y))
    elif anchors:
        anchor, component = anchors[0]
        t = Transform(*component.transformation)
        anchor_data[anchor.name] = t.transformPoint((anchor.x, anchor.y))
Get data for an anchor from a list of components.