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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def load_emacs_open_in_editor_bindings():
 """ Pressing C-X C-E will open the buffer in an external editor. """

    registry = Registry()

    registry.add_binding(Keys.ControlX, Keys.ControlE,
                         filter=EmacsMode() & ~HasSelection())(
         get_by_name('edit-and-execute-command'))

    return registry