删除无用代码并且新增流程图相关内容

flowchart/urls/__init__.py

@@ -0,0 +1 @@
+# URLs package

flowchart/urls/oj.py

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+from django.urls import path
+from ..views.oj import (
+    FlowchartSubmissionAPI,
+    FlowchartSubmissionListAPI,
+    FlowchartSubmissionRetryAPI
+)
+
+urlpatterns = [
+    path('flowchart/submission', FlowchartSubmissionAPI.as_view()),
+    path('flowchart/submissions', FlowchartSubmissionListAPI.as_view()),
+    path('flowchart/submission/retry', FlowchartSubmissionRetryAPI.as_view()),
+]