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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 _get_tool_str(self, tool):
 """ get a string representation of the tool """

        res = tool['file'] 
        try:
            res += '.' + tool['function']
        except Exception as ex:
            print('Warning - no function defined for tool ' + str(tool))
        res += '\n'
        return res