This requires knowledge of both languages. If you don't know Python, and have nobody to help you, you can try AI.
I've prompted your request to an AI, and this was the result. Keep in mind that this might not work because of some silly errors. It will need to be adjusted, which means you need to Google the commands used etc.
import numpy as np
from mpl_toolkits.mplot3d.art3d import Poly3DCollection
from stl import mesh
# clear all previous commands
np.random.seed(0)
np.set_printoptions(precision=3, suppress=True)
# variable you can change
SizeL = 20
Def = 160
SFact = (SizeL/2)/np.pi
A = SFact*np.pi
D = A/Def
X,Y,Z = np.meshgrid(np.arange(-A, A+D, D),
np.arange(-A, A+D, D),
np.arange(-A, A+D, D))
OBJ = np.sin(Y/SFact) + np.cos(Y/SFact) * np.sin(Z/SFact) \
+ np.cos(Z/SFact) * np.sin(X/SFact) + 0
T = 0.5
OBJ = ((OBJ-T)*(OBJ+T))
iso_surface = np.isosurface(OBJ, level=0)
F1, V1 = iso_surface.triangles, iso_surface.vertices
iso_caps = np.isocaps(OBJ, level=0, direction='below')
F2, V2 = iso_caps.triangles, iso_caps.vertices
F3 = np.vstack((F1, F2 + len(V1)))
V3 = np.vstack((V1, V2))
fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
mesh = Poly3DCollection(V3[F3])
mesh.set_facecolor('red')
ax.add_collection3d(mesh)
ax.set_xlabel('X')
ax.set_ylabel('Y')
ax.set_zlabel('Z')
ax.set_box_aspect([1,1,1])
ax.view_init(30, 30)
plt.show()
mesh = mesh.Mesh(np.zeros(F3.shape[0], dtype=mesh.Mesh.dtype))
for i, f in enumerate(F3):
for j in range(3):
mesh.vectors[i][j] = V3[f[j], :]
mesh.save('Gyroid-network1.stl')
Hope I helped.
