(a) A person is guilty of an attempt to commit a crime if, with the intent to commit a specific offense, he does any overt act towards the commission of such offense.
(b) It is no defense under this section that the offense charged to have been attempted was, under the attendant circumstances, factually or legally impossible of commission, if such offense could have been committed had the attendant circumstances been as the defendant believed them to be.
(c) A person is not liable under this section if, under circumstances manifesting a voluntary and complete renunciation of this criminal intent, he avoided the commission of the offense attempted by abandoning his criminal effort and, if mere abandonment is insufficient to accomplish such avoidance, by taking further and affirmative steps which prevented the commission thereof. The burden of injecting this issue is on the defendant, but this does not shift the burden of proof.
(d) An attempt is a:
(1) Class A felony if the offense attempted is murder.
(2) Class B felony if the offense attempted is a Class A felony.
(3) Class C felony if the offense attempted is a Class B felony.
(4) Class A misdemeanor if the offense attempted is a Class C felony.
(5) Class B misdemeanor if the offense attempted is a Class A misdemeanor.
(6) Class C misdemeanor if the offense attempted is a Class B misdemeanor.
(7) Violation if the offense attempted is a Class C misdemeanor.