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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 _transform_positioning(ha, va):
 """Converts matplotlib positioning to pgf node positioning. Not quite accurate but the results are equivalent more or less."""

    if ha == "center" and va == "center":
        return None

    ha_mpl_to_tikz = {"right": "east", "left": "west", "center": ""}
    va_mpl_to_tikz = {
        "top": "north",
        "bottom": "south",
        "center": "",
        "baseline": "base",
    }
    return "anchor={} {}".format(va_mpl_to_tikz[va], ha_mpl_to_tikz[ha]).strip()