What does papanatas mean?

The word papanatas in Spanish refers to a simple person , very credulous, or naive, easy to deceive and who can be astonished or surprised by anything, it is also known as a fool, bob, flycatcher or brat.
This word in its etymology comes from the transitive active verb «papar» and the noun «nata», from the old Spanish «natta».
Example sentence:
‘Pedro is a fool, he thinks he knows so much and they fooled him’ is translated as ‘Pedro es un papanatas, él se cree que sabe tanto y lo engañaron.’