[Update] Move the import of control into the __init__().

gklearn/kernels/sylvester_equation.py

@@ -14,7 +14,6 @@ import sys
 from gklearn.utils import get_iters
 import numpy as np
 import networkx as nx
-from control import dlyap
 from gklearn.utils.parallel import parallel_gm, parallel_me
 from gklearn.kernels import RandomWalkMeta
 
@@ -23,6 +22,7 @@ class SylvesterEquation(RandomWalkMeta):
 
 
 	def __init__(self, **kwargs):
+		from control import dlyap
 		super().__init__(**kwargs)