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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 str_repl(self, inputstring, **kwargs):
 """Add back strings."""

        out = []
        comment = None
        string = None

        for i, c in enumerate(append_it(inputstring, None)):
            try:

                if comment is not None:
                    if c is not None and c in nums:
                        comment += c
                    elif c == unwrapper and comment:
                        ref = self.get_ref("comment", comment)
                        if out and not out[-1].endswith("\n"):
                            out[-1] = out[-1].rstrip(" ")
                            if not self.minify:
                                out[-1] += "  "  # put two spaces before comment
                        out.append("#" + ref)
                        comment = None
                    else:
                        raise CoconutInternalException("invalid comment marker in", getline(i, inputstring))
                elif string is not None:
                    if c is not None and c in nums:
                        string += c
                    elif c == unwrapper and string:
                        text, strchar = self.get_ref("str", string)
                        out.append(strchar + text + strchar)
                        string = None
                    else:
                        raise CoconutInternalException("invalid string marker in", getline(i, inputstring))
                elif c is not None:
                    if c == "#":
                        comment = ""
                    elif c == strwrapper:
                        string = ""
                    else:
                        out.append(c)

            except CoconutInternalException as err:
                complain(err)
                if comment is not None:
                    out.append(comment)
                    comment = None
                if string is not None:
                    out.append(string)
                    string = None
                out.append(c)

        return "".join(out)