'Search for the icon corresponding to one command.'

def _lookup_icon(self, name):

    self.icons_files[name] = None
    if os.path.isabs(name):
        (root, ext) = os.path.splitext(name)
        if (ext == '.png'):
            self.icons_files[name] = (name if os.path.isfile(name) else None)
        else:
            self.icons_files[name] = ((name + '.png') if os.path.isfile((name + '.png')) else None)
    else:
        self.icons_files[name] = getIconPath(name)
    if (self.icons_files[name] is None):
        self.icons_files[name] = self.default_icon
