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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 count_empty(self, field):
 """ List of empty row indices """

        try:
            df2 = self.df[[field]]
            vals = where(df2.applymap(lambda x: x == ''))
            num = len(vals[0])
        except Exception as e:
            self.err(e, "Can not count empty values")
            return
        self.ok("Found", num, "empty rows in column " + field)