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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_alignment(self, pys_style):
 """Returns xlwt.Alignment for pyspread style"""


        # Return None if there is no alignment
        alignment_styles = ["justification", "vertical_align", "angle"]
        if not any(astyle in pys_style for astyle in alignment_styles):
            return

        def angle2xfrotation(angle):
            """Returns angle from xlrotatation"""

            # angle is counterclockwise
            if 0 <= angle <= 90:
                return angle

            elif -90 <= angle < 0:
                return 90 - angle

            return 0

        justification2xfalign = {
            "left": 1,
            "center": 2,
            "right": 3,
        }

        vertical_align2xfalign = {
            "top": 0,
            "middle": 1,
            "bottom": 2,
        }

        alignment = xlwt.Alignment()

        try:
            alignment.horz = justification2xfalign[pys_style["justification"]]

        except KeyError:
            pass

        try:
            alignment.vert = \
                vertical_align2xfalign[pys_style["vertical_align"]]

        except KeyError:
            pass

        try:
            alignment.rota = angle2xfrotation(pys_style["angle"])

        except KeyError:
            pass

        return alignment