$post_author: WP_User Object
(
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            [user_login] => robert-wenzel
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            [user_email] => [email protected]
            [user_url] => 
            [user_registered] => 2011-12-07 15:12:04
            [user_activation_key] => 
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            [display_name] => Robert Wenzel
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get_the_author_meta: 

$bio: Robert Wenzel is Editor & Publisher of EconomicPolicyJournal.com and author of The Fed Flunks: My Speech at the New York Federal Reserve Bank.

$bios: Array
(
    [0] => Robert Wenzel is Editor & Publisher of EconomicPolicyJournal.com and author of The Fed Flunks: My Speech at the New York Federal Reserve Bank.
)