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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 _get_pattern(self, pys_style):
 """Returns xlwt.pattern for pyspread style"""


        # Return None if there is no bgcolor
        if "bgcolor" not in pys_style:
            return

        pattern = xlwt.Pattern()
        pattern.pattern = xlwt.Pattern.SOLID_PATTERN

        bgcolor = wx.Colour()
        bgcolor.SetRGB(pys_style["bgcolor"])
        pattern.pattern_fore_colour = self.color2idx(*bgcolor.Get())

        return pattern