I want to take out a set of nodes in the grid and the corresponding temperature at the nodes to make a graph, but I ran into this error and don't know how to fix it？

Errors
1

I want to get a set of nodes and take out the temperature values at those nodes to plot it：
here is part of my code:

from fenics import *
import matplotlib.pyplot as plt
import numpy as np
import csv
import os

mesh = Mesh()
with XDMFFile("mesh_5um/mesh_5um.xdmf") as infile:
    infile.read(mesh)
    
H = FunctionSpace(mesh, 'P', 1)

t=150

T=Function(H)

timeseries_T = TimeSeries('Couple_heat_transfer/temperature_series')
timeseries_T.retrieve(T.vector(), t) 

T = plot(T)
plt.colorbar(T)
plt.show()

nodes = np.concatenate([np.linspace(0 + DOLFIN_EPS, 3e-8 - DOLFIN_EPS, num=500),np.linspace(3e-8 + DOLFIN_EPS, 2e-6 - DOLFIN_EPS, num=200),np.linspace(2e-6 + DOLFIN_EPS, 10e-6 - DOLFIN_EPS, num=200)])

vertices = []
for i in nodes:
    if i not in vertices:
        vertices. append(i)

points = [(y_, 2.5e-6) for y_ in vertices]

T_line = np.array([T(point) for point in points])

Here is the error：

TypeError                                 Traceback (most recent call last)
<ipython-input-2-78d0c7048095> in <module>
     35 points = [(y_, 2.5e-6) for y_ in vertices]
     36 #print('points',points)
---> 37 T_line = np.array([T(point) for point in points])
     38 

<ipython-input-2-78d0c7048095> in <listcomp>(.0)
     35 points = [(y_, 2.5e-6) for y_ in vertices]
     36 #print('points',points)
---> 37 T_line = np.array([T(point) for point in points])
     38 

TypeError: 'TriContourSet' object is not callable

I do not know how to remove this error.
Please help me.

2

You overwrite the variable T here