findAt(): This method returns the object or objects in the VertexArray located at the given coordinates.

   findAt initially uses the ACIS tolerance of 1E-6. As a result, findAt returns any Vertex object that is at the arbitrary point specified or at a distance of less than 1E-6 from the arbitrary point. If nothing is found, findAt uses the tolerance for imprecise geometry (applicable only for imprecise geometric entities).

    findAt will always try to find objects among all the vertices in the part or assembly instance and will not restrict itself to a subset even if the VertexArray represents such subset.

    Required argument:coordinates A sequence of Floats specifying the X-, Y-, and Z-coordinates of the object to find.

    findAt returns either a Vertex object or a sequence of Vertex objects based on the type of input.

    If coordinates is a sequence of Floats, findAt returns the Vertex object at that point.If you omit the coordinates keyword argument, findAt accepts as arguments a sequence of sequence of floats in the     following format:

verts = v.findAt(((20.19686, -169.513997, 27.798593), ),

                 ((19.657627, -167.295749, 27.056402), ),

                 ((18.274129, -157.144741, 25.15218), ))

Return value:A Vertex object or a sequence of Vertex objects.

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