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![Tango pcb layout software Tango pcb layout software](https://bayareacircuits.com/wp-content/uploads/2016/08/pcb-creator-3.jpg)
XML is one way to transfer a Printed Circuit Board (PCB) data basebetween Software Applications. This projects starts with an exportfrom PCB123 and creates a Kicad brd file. This projects starts with an exportfrom PCB123 and creates a Kicad brd file.
I would not recommend trying to import gerbers. While a gerber will contain all the geometry, it won't contain any of the semantic data concerning net and component names. I don't think there's a solution for converting directly from Tango to Eagle format, but these two programs should hopefully be able to get you most of the way. The first one will convert the Tango file to the format used by the open source EDA software KiCAD.
The second second one will convert a KiCAD files to Eagle's format, assuming it isn't broken.