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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 _reorderForPreference(themeList, preferredThemeName):
 """ Re-order the input themeList according to the preferred theme. Returns None. """

    for theme in themeList:
        if preferredThemeName == theme.themeName:
            themeList.remove(theme)
            themeList.insert(0, theme)
            return