<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def upregulated(self, thresh=0.05, idx=True):
 """ Upregulated features. {threshdoc} """

        ind = (
            (self.data[self.pval_column] <= thresh)
            & (self.data[self.lfc_column] > 0)
        )
        if idx:
            return ind
        return self[ind]