Convert this language to Context Free Grammar
If you need to prove the language is context-free, showing a PDA that accepts $L$ is enough.

Sometimes, formulating the rules that generate exactly the language $L$ is not so trivial; in such cases you can start by a constructing the PDA that accepts $L$, then convert it to a CFG.

The transformation PDA $\rightarrow$ CFG can be found:

Lecture notes

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