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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 attrfindrows(self, groupname, attrname, value):
 """Get the row numbers of all rows where the attribute matches the given value."""

        values = self.attrgetcol(groupname, attrname)
        return [i for i in range(len(values)) if values[i] == value]