Question: n epsi - free PDA is a PDA with two modifications: that does not have any epsi transitions ( having epsi for

n \epsi -free PDA is a PDA with two modifications:
that does not have any \epsi transitions (having \epsi for stack actions is OK), and
it can push multiple symbols in one transition (however it can pop at most one symbol per transition).
That is,(Q,\Sigma ,\Gamma ,\delta , q0 F) is an \epsi -free PDA iff it is a PDA with the following modified transition function:
\delta : Q \times \Sigma \times \Gamma \epsi -> P (Q \times \Gamma ).
Here, P (A) is the powerset of A that contains only finite sets. Note that there are 2 differences to \delta :
1. The second argument of \delta cannot be \epsi .
2.q in Q,\sigma in \Sigma ,\gamma in \Gamma \epsi .\delta (q,\sigma ,\gamma ) returns a finite set of pairs made up of a state, and a sequence of symbols
from the stack alphabet (as opposed to a state and a single stack symbol or \epsi from the definition of a normal
PDA).
The accepting criterion for \epsi -free PDA follow the same form presented for PDA in the lectures.
Prove or disprove: the class of languages \epsi -free PDA recognize is the class of context-free languages.

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