title: Getting "AssertionError: duplicate Parameters found" when I hit /swagger url
body: <p>I am implementing swagger using <a href="https://github.com/axnsan12/drf-yasg/#id11" rel="noreferrer">drf-yasg</a> for django rest framework APIs in my project.</p>
  <p>I follow the quick start section of drf-yasg. When I hit /swagger gets AssertionError: duplicate Parameters found. Below is my code and traceback.</p>
  <p><strong>urls.py</strong></p>
  <pre><code>from drf_yasg.views import get_schema_view
  from drf_yasg import openapi
  
  schema_view = get_schema_view(
     openapi.Info(
        title=&quot;Snippets API&quot;,
        default_version='v1',
        description=&quot;Test description&quot;,
        terms_of_service=&quot;https://www.google.com/policies/terms/&quot;,
        contact=openapi.Contact(email=&quot;contact@snippets.local&quot;),
        license=openapi.License(name=&quot;BSD License&quot;),
     ),
     public=True,
     permission_classes=(permissions.AllowAny,),
  )
  
  urlpatterns = [
      url(r'^swagger(?P&lt;format&gt;\.json|\.yaml)$', schema_view.without_ui(cache_timeout=0), name='schema-json'),
      url(r'^swagger/$', schema_view.with_ui('swagger', cache_timeout=0), name='schema-swagger-ui'),
      url(r'^redoc/$', schema_view.with_ui('redoc', cache_timeout=0), name='schema-redoc'),
      # path('graphql', csrf_exempt(GraphQLObservableUnboxingView.as_view(graphiql=True, schema=schema))),
  ]
  </code></pre>
  <p><strong>Traceback</strong></p>
  <pre><code>
  ```Traceback (most recent call last):
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/django/core/handlers/exception.py&quot;, line 34, in inner
      response = get_response(request)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/django/core/handlers/base.py&quot;, line 115, in _get_response
      response = self.process_exception_by_middleware(e, request)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/django/core/handlers/base.py&quot;, line 113, in _get_response
      response = wrapped_callback(request, *callback_args, **callback_kwargs)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/django/views/decorators/csrf.py&quot;, line 54, in wrapped_view
      return view_func(*args, **kwargs)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/django/views/generic/base.py&quot;, line 71, in view
      return self.dispatch(request, *args, **kwargs)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/rest_framework/views.py&quot;, line 505, in dispatch
      response = self.handle_exception(exc)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/rest_framework/views.py&quot;, line 465, in handle_exception
      self.raise_uncaught_exception(exc)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/rest_framework/views.py&quot;, line 476, in raise_uncaught_exception
      raise exc
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/rest_framework/views.py&quot;, line 502, in dispatch
      response = handler(request, *args, **kwargs)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/views.py&quot;, line 94, in get
      schema = generator.get_schema(request, self.public)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/generators.py&quot;, line 254, in get_schema
      paths, prefix = self.get_paths(endpoints, components, request, public)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/generators.py&quot;, line 412, in get_paths
      operation = self.get_operation(view, path, prefix, method, components, request)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/generators.py&quot;, line 454, in get_operation
      operation = view_inspector.get_operation(operation_keys)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/inspectors/view.py&quot;, line 36, in get_operation
      parameters = self.add_manual_parameters(parameters)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/inspectors/view.py&quot;, line 172, in add_manual_parameters
      return merge_params(parameters, manual_parameters)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/utils.py&quot;, line 282, in merge_params
      parameters = param_list_to_odict(parameters)
    File &quot;/home/abc/development/sw_api/env_sw_api_python3.7/lib/python3.7/site-packages/drf_yasg/utils.py&quot;, line 267, in param_list_to_odict
      assert len(result) == len(parameters), &quot;duplicate Parameters found&quot;
  AssertionError: duplicate Parameters found
  
  </code></pre>