def __init__(self):
		'''创建表'''
		self.conn = sqlite3.connect("./items.db")
		if VERBOSE:
			print 'Database connection OPEN.'
		# Domain 表
		self.conn.execute(CTABLE_DOMAIN)
		# Website 表
		self.conn.execute(CTABLE_WEBSITE)
		# Rule 表 
		self.conn.execute(CTABLE_RULESETS)

		self.conn.commit()
		if VERBOSE:
			cur = self.conn.cursor()
			print 'Tables:',cur.execute("SELECT name FROM sqlite_master WHERE type = 'table'").fetchall()
def _create_3d_axis():
    """creates a subplot with 3d projection if one does not already exist"""
    from matplotlib.projections import get_projection_class
    from matplotlib import _pylab_helpers

    create_axis = True
    if _pylab_helpers.Gcf.get_active() is not None:
        if isinstance(plt.gca(), get_projection_class('3d')):
            create_axis = False
    if create_axis:
        plt.figure()
        plt.subplot(111, projection='3d')