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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 write_cell(self, x, y, value, style=None):
 """ writing style and value in the cell of x and y position """

        if isinstance(style, str):
            style = self.xlwt.easyxf(style)
        if style:
            self._sheet.write(x, y, label=value, style=style)
        else:
            self._sheet.write(x, y, label=value)