fix(examples) import 'u'-prefixed versions of modules (#2365)

import usys and utime instead of sys and time, as the latter are not available on all platforms

examples/widgets/chart/lv_example_chart_7.py

@@ -1,5 +1,5 @@
 #!/opt/bin/lv_micropython -i
-import time
+import utime as time
 import lvgl as lv
 import display_driver
 

examples/widgets/img/lv_example_img_1.py

@@ -1,5 +1,5 @@
 #!/opt/bin/lv_micropython -i
-import sys
+import usys as sys
 import lvgl as lv
 import display_driver
 from imagetools import get_png_info, open_png

examples/widgets/img/lv_example_img_2.py

@@ -1,5 +1,5 @@
 #!/opt/bin/lv_micropython -i
-import sys
+import usys as sys
 import lvgl as lv
 import display_driver
 from imagetools import get_png_info, open_png

examples/widgets/img/lv_example_img_3.py

@@ -1,5 +1,5 @@
 #!/opt/bin/lv_micropython -i
-import sys
+import usys as sys
 import lvgl as lv
 import display_driver
 from imagetools import get_png_info, open_png

examples/widgets/meter/lv_example_meter_1.py

@@ -1,5 +1,5 @@
 #!//opt/bin/lv_micropython -i
-import time
+import utime as time
 import lvgl as lv
 import display_driver
 

examples/widgets/meter/lv_example_meter_2.py

@@ -1,5 +1,5 @@
 #!//opt/bin/lv_micropython -i
-import time
+import utime as time
 import lvgl as lv
 import display_driver
 

examples/widgets/meter/lv_example_meter_3.py

@@ -1,5 +1,5 @@
 #!//opt/bin/lv_micropython -i
-import time
+import utime as time
 import lvgl as lv
 import display_driver
 from imagetools import get_png_info, open_png

examples/widgets/roller/lv_example_roller_3.py

@@ -1,8 +1,8 @@
 #!/opt/bin/lv_micropython -i
-import time
+import utime as time
 import lvgl as lv
 import display_driver
-import sys
+import usys as sys
 
 class Lv_Roller_3():