How gen I get the exact Operator through libclang?


I would like to use libclang to parse C code (actually I am using the Python binding).

With the help of Cursors I can get the kind of the AST-nodes / cursors.
If I have a binary operation like: "a = b;" i get the kind "BINARY_OPERATION".
But how can I get the information that this is an "assignment" (and not an "addition" for example)?