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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 resolvePrefix(self):
 """ extract prefix information into dict with the key of '_prefixstr' """

        tmpstrlist = []
        tmpstodict = {}
        for line in self.file_lines:
            if line.startswith('%'):
                stolist = line.replace('%', '').split('sto')
                rpnexp = stolist[0].strip()  # rpn expression
                rpnvar = stolist[1].strip()  # rpn variable
                tmpstodict[rpnvar] = rpnexp
                # bug: rpnval in rpnexp
                # raises error when converting string convert to float
                # Found: 2016-06-08 22:29:25 PM CST
                # Fixed: 2016-06-12 11:51:01 AM CST
                # e.g.
                # a sto 0.1
                # a sto b
                # then b should be 0.1,
                # i.e. b -> a -> 0.1
                # solve the 'sto chain' assignment issue.

        self.stodict = self.resolve_rpn(tmpstodict)
        for k, v in self.stodict.items():
            stostr = '% {val} sto {var}'.format(val=v, var=k)
            tmpstrlist.append(stostr)
        self.prestrdict['_prefixstr'] = tmpstrlist