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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 do_hdr(self, line, hdrs_usr):
 """Initialize self.h2i."""

        # If there is no header hint, consider the first line the header.
        if self.hdr_ex is None:
            self._init_hdr(line, hdrs_usr)
            return True
        # If there is a header hint, examine each beginning line until header hint is found.
        elif self.hdr_ex in line:
            self._init_hdr(line, hdrs_usr)
            return True
        return False