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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 mutapply(self, function, fieldname):
 """ Applies `function` in-place to the field name specified. In other words, `mutapply` overwrites column `fieldname` ith the results of applying `function` to each element of that column. """

        self[fieldname] = self.apply(function, fieldname)