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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_for(self, dynamic_part):
 """ Return a variation of the current dynamic field based on the given dynamic part. Use the "format" attribute to create the final name """

        if not hasattr(self, '_instance'):
            raise ImplementationError('"get_for" can be used only on a bound field')
        name = self.get_name_for(dynamic_part)
        return self._instance.get_field(name)