[DOCS] Use return type of TEXT rather than varchar[] is better for me!

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Page: https://www.postgresql.org/docs/9.0/static/plpython-data.html
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In section 42.3 on page:
https://www.postgresql.org/docs/9.0/static/plpython-data.html

if I use a return type TEXT I get a string of text, as probably desired!