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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 markInputline( self, markerString = ">!<" ):
 """Extracts the exception line from the input string, and marks the location of the exception with a special symbol. """

        line_str = self.line
        line_column = self.column - 1
        if markerString:
            line_str = "".join((line_str[:line_column],
                                markerString, line_str[line_column:]))
        return line_str.strip()