tests/digital: add missing function import

Signed-off-by: Adrian Stanea <[email protected]>

tests/m2k_digital_test.py

@@ -20,8 +20,16 @@
 
 import unittest
 import libm2k
-from digital_functions import set_digital_trigger, check_digital_channels_state, check_digital_output, \
-    check_digital_trigger, check_open_drain_mode, test_kernel_buffers, test_pattern_generator_pulse
+from digital_functions import (
+    check_digital_channels_state,
+    check_digital_output,
+    check_digital_trigger,
+    check_open_drain_mode,
+    set_digital_trigger,
+    test_kernel_buffers,
+    test_last_sample_hold,
+    test_pattern_generator_pulse,
+)
 from digital_functions import test_digital_cyclic_buffer
 import reset_def_values as reset
 from open_context import ctx, dig, d_trig
@@ -101,4 +109,4 @@ def test_last_sample_hold(self):
         # All channels
         result_ok = test_last_sample_hold(dig, d_trig, ctx, None)
         with self.subTest(msg="DIO all"):
-            self.assertEqual(result_ok, True, f"Failed to hold the last sample on all DIO test")
+            self.assertEqual(result_ok, True, f"Failed to hold the last sample on all DIO test")