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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 put_abs (self, r, c, ch):
        '''Screen array starts at 1 index.'''

        r = constrain (r, 1, self.rows)
        c = constrain (c, 1, self.cols)
        if isinstance(ch, bytes):
            ch = self._decode(ch)[0]
        else:
            ch = ch[0]
        self.w[r-1][c-1] = ch