python区域掩膜白话，显示目标区域

def shp2clip(originfig,ax,shpfile,region):
    sf = shp.Reader(shpfile)
    vertices = []
    codes = []
    for shape_rec in sf.shapeRecords():
        if shape_rec.record[2] in region:  # 对应数字要找到
            pts = shape_rec.shape.points
            prt = list(shape_rec.shape.parts) + [len(pts)]
            for i in range(len(prt) - 1):
                for j in range(prt[i], prt[i + 1]):
                    vertices.append((pts[j][0], pts[j][1]))
                codes += [Path.MOVETO]
                codes += [Path.LINETO] * (prt[i + 1] - prt[i] - 2)
                codes += [Path.CLOSEPOLY]
            clip1 = Path(vertices, codes)
            clip2 = PathPatch(clip1, transform=ax.transData)
    for contour in originfig.collections:
        contour.set_clip_path(clip2)
    return clip2

这是选择shp文件的代码

import shapefile as shp
import matplotlib.pyplot as plt
import numpy as np
import xarray as xr
f