Entrapment happens long before a warrant is ever signed.
Entrapment is used so a warrant can be issued. Or at least that is how it used to work.
Entrapment is defined as a situation in which a normally law-abiding individual is induced into committing a criminal act they otherwise would not have committed because of overbearing harassment, fraud, flattery or threats made by an official police source.
ETA: Officers in a sting operation are allowed to conduct certain actions, such as presenting an opportunity to commit a crime, initiating contact, and even telling the person that the operation is not a set up. However, these officers cannot cross the line and overly pressure someone into committing a crime, pester them, or falsely tell them that the act is legal.
I don't claim I'm the smartest person in the world, but smarter than Trump, no big deal.
Person, woman, man, camera, TV, idiot.
See, I even remember one more than 45.