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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _init_idxs_int(self, usr_hdrs):
 """List of indexes whose values will be ints."""

        self.idxs_int = [
            Idx for Hdr, Idx in self.hdr2idx.items() if Hdr in usr_hdrs and Hdr in self.int_hdrs]