chore: regens API reference docs (#889)

diff --git a/docs/dyn/serviceconsumermanagement_v1.services.tenancyUnits.html b/docs/dyn/serviceconsumermanagement_v1.services.tenancyUnits.html
index 216fdf7..18aa84d 100644
--- a/docs/dyn/serviceconsumermanagement_v1.services.tenancyUnits.html
+++ b/docs/dyn/serviceconsumermanagement_v1.services.tenancyUnits.html
@@ -75,49 +75,49 @@
 <h1><a href="serviceconsumermanagement_v1.html">Service Consumer Management API</a> . <a href="serviceconsumermanagement_v1.services.html">services</a> . <a href="serviceconsumermanagement_v1.services.tenancyUnits.html">tenancyUnits</a></h1>
 <h2>Instance Methods</h2>
 <p class="toc_element">
-  <code><a href="#addProject">addProject(parent, body, x__xgafv=None)</a></code></p>
+  <code><a href="#addProject">addProject(parent, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Add a new tenant project to the tenancy unit.</p>
 <p class="toc_element">
-  <code><a href="#applyProjectConfig">applyProjectConfig(name, body, x__xgafv=None)</a></code></p>
+  <code><a href="#applyProjectConfig">applyProjectConfig(name, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Apply a configuration to an existing tenant project.</p>
 <p class="toc_element">
-  <code><a href="#attachProject">attachProject(name, body, x__xgafv=None)</a></code></p>
+  <code><a href="#attachProject">attachProject(name, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Attach an existing project to the tenancy unit as a new tenant</p>
 <p class="toc_element">
-  <code><a href="#create">create(parent, body, x__xgafv=None)</a></code></p>
+  <code><a href="#create">create(parent, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Creates a tenancy unit with no tenant resources.</p>
 <p class="toc_element">
   <code><a href="#delete">delete(name, x__xgafv=None)</a></code></p>
 <p class="firstline">Delete a tenancy unit. Before you delete the tenancy unit, there should be</p>
 <p class="toc_element">
-  <code><a href="#deleteProject">deleteProject(name, body, x__xgafv=None)</a></code></p>
+  <code><a href="#deleteProject">deleteProject(name, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Deletes the specified project resource identified by a tenant resource tag.</p>
 <p class="toc_element">
-  <code><a href="#list">list(parent, pageToken=None, x__xgafv=None, pageSize=None, filter=None)</a></code></p>
+  <code><a href="#list">list(parent, pageSize=None, pageToken=None, x__xgafv=None, filter=None)</a></code></p>
 <p class="firstline">Find the tenancy unit for a managed service and service consumer.</p>
 <p class="toc_element">
   <code><a href="#list_next">list_next(previous_request, previous_response)</a></code></p>
 <p class="firstline">Retrieves the next page of results.</p>
 <p class="toc_element">
-  <code><a href="#removeProject">removeProject(name, body, x__xgafv=None)</a></code></p>
+  <code><a href="#removeProject">removeProject(name, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Removes the specified project resource identified by a tenant resource tag.</p>
 <p class="toc_element">
-  <code><a href="#undeleteProject">undeleteProject(name, body, x__xgafv=None)</a></code></p>
+  <code><a href="#undeleteProject">undeleteProject(name, body=None, x__xgafv=None)</a></code></p>
 <p class="firstline">Attempts to undelete a previously deleted tenant project. The project must</p>
 <h3>Method Details</h3>
 <div class="method">
-    <code class="details" id="addProject">addProject(parent, body, x__xgafv=None)</code>
+    <code class="details" id="addProject">addProject(parent, body=None, x__xgafv=None)</code>
   <pre>Add a new tenant project to the tenancy unit.
 There can be a maximum of 512 tenant projects in a tenancy unit.
 If there are previously failed `AddTenantProject` calls, you might need to
 call `RemoveTenantProject` first to resolve them before you can make
 another call to `AddTenantProject` with the same tag.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   parent: string, Name of the tenancy unit.
 Such as 'services/service.googleapis.com/projects/12345/tenancyUnits/abcd'. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request to add a newly created and configured tenant project to a tenancy
@@ -140,7 +140,7 @@
         ],
         "accountId": "A String", # ID of the IAM service account to be created in tenant project.
             # The email format of the service account is
-            # "<account-id>@<tenant-project-id>.iam.gserviceaccount.com".
+            # "&lt;account-id&gt;@&lt;tenant-project-id&gt;.iam.gserviceaccount.com".
             # This account ID must be unique within tenant project and service
             # producers have to guarantee it. The ID must be 6-30 characters long, and
             # match the following regular expression: `[a-z]([-a-z0-9]*[a-z0-9])`.
@@ -233,7 +233,7 @@
 </div>
 
 <div class="method">
-    <code class="details" id="applyProjectConfig">applyProjectConfig(name, body, x__xgafv=None)</code>
+    <code class="details" id="applyProjectConfig">applyProjectConfig(name, body=None, x__xgafv=None)</code>
   <pre>Apply a configuration to an existing tenant project.
 This project must exist in an active state and have the original owner
 account. The caller must have permission to add a project to the given
@@ -250,12 +250,12 @@
 folder isn't supported.
 The operation fails if any of the steps fail, but no rollback of already
 applied configuration changes is attempted.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   name: string, Name of the tenancy unit.
 Such as 'services/service.googleapis.com/projects/12345/tenancyUnits/abcd'. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request to apply configuration to an existing tenant project.
@@ -276,7 +276,7 @@
         ],
         "accountId": "A String", # ID of the IAM service account to be created in tenant project.
             # The email format of the service account is
-            # "<account-id>@<tenant-project-id>.iam.gserviceaccount.com".
+            # "&lt;account-id&gt;@&lt;tenant-project-id&gt;.iam.gserviceaccount.com".
             # This account ID must be unique within tenant project and service
             # producers have to guarantee it. The ID must be 6-30 characters long, and
             # match the following regular expression: `[a-z]([-a-z0-9]*[a-z0-9])`.
@@ -369,7 +369,7 @@
 </div>
 
 <div class="method">
-    <code class="details" id="attachProject">attachProject(name, body, x__xgafv=None)</code>
+    <code class="details" id="attachProject">attachProject(name, body=None, x__xgafv=None)</code>
   <pre>Attach an existing project to the tenancy unit as a new tenant
 resource. The project could either be the tenant project reserved by
 calling `AddTenantProject` under a tenancy unit of a service producer's
@@ -380,12 +380,12 @@
 folder. Make sure the ServiceConsumerManagement service account is
 the owner of that project. These two requirements are already met
 if the project is reserved by calling `AddTenantProject`.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   name: string, Name of the tenancy unit that the project will be attached to.
 Such as 'services/service.googleapis.com/projects/12345/tenancyUnits/abcd'. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request to attach an existing project to the tenancy unit as a new tenant
@@ -454,8 +454,12 @@
 </div>
 
 <div class="method">
-    <code class="details" id="create">create(parent, body, x__xgafv=None)</code>
+    <code class="details" id="create">create(parent, body=None, x__xgafv=None)</code>
   <pre>Creates a tenancy unit with no tenant resources.
+If tenancy unit already exists, it will be returned,
+however, in this case, returned TenancyUnit does not have tenant_resources
+field set and ListTenancyUnit has to be used to get a complete
+TenancyUnit with all fields populated.
 
 Args:
   parent: string, services/{service}/{collection id}/{resource id}
@@ -464,7 +468,7 @@
 {resource id} is the consumer numeric id, such as project number: '123456'.
 {service} the name of a managed service, such as 'service.googleapis.com'.
 Enables service binding using the new tenancy unit. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request to create a tenancy unit for a service consumer of a managed service.
@@ -512,7 +516,7 @@
     <code class="details" id="delete">delete(name, x__xgafv=None)</code>
   <pre>Delete a tenancy unit. Before you delete the tenancy unit, there should be
 no tenant resources in it that aren't in a DELETED state.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   name: string, Name of the tenancy unit to be deleted. (required)
@@ -570,7 +574,7 @@
 </div>
 
 <div class="method">
-    <code class="details" id="deleteProject">deleteProject(name, body, x__xgafv=None)</code>
+    <code class="details" id="deleteProject">deleteProject(name, body=None, x__xgafv=None)</code>
   <pre>Deletes the specified project resource identified by a tenant resource tag.
 The mothod removes a project lien with a 'TenantManager' origin if that was
 added. It will then attempt to delete the project. If that operation fails,
@@ -580,12 +584,12 @@
 `RemoveTenantProject` method.
 New resources with the same tag can't be added if there are existing
 resources in a DELETED state.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   name: string, Name of the tenancy unit.
 Such as 'services/service.googleapis.com/projects/12345/tenancyUnits/abcd'. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request message to delete tenant project resource from the tenancy unit.
@@ -646,7 +650,7 @@
 </div>
 
 <div class="method">
-    <code class="details" id="list">list(parent, pageToken=None, x__xgafv=None, pageSize=None, filter=None)</code>
+    <code class="details" id="list">list(parent, pageSize=None, pageToken=None, x__xgafv=None, filter=None)</code>
   <pre>Find the tenancy unit for a managed service and service consumer.
 This method shouldn't be used in a service producer's runtime path, for
 example to find the tenant project number when creating VMs. Service
@@ -660,6 +664,7 @@
 service consumer, for example 'projects', or 'organizations'.
 {resource id} is the consumer numeric id, such as project number: '123456'.
 {service} the name of a service, such as 'service.googleapis.com'. (required)
+  pageSize: integer, The maximum number of results returned by this request.
   pageToken: string, The continuation token, which is used to page through large result sets.
 To get the next page of results, set this parameter to the value of
 `nextPageToken` from the previous response.
@@ -667,7 +672,6 @@
     Allowed values
       1 - v1 error format
       2 - v2 error format
-  pageSize: integer, The maximum number of results returned by this request.
   filter: string, Filter expression over tenancy resources field. Optional.
 
 Returns:
@@ -715,7 +719,7 @@
 </div>
 
 <div class="method">
-    <code class="details" id="removeProject">removeProject(name, body, x__xgafv=None)</code>
+    <code class="details" id="removeProject">removeProject(name, body=None, x__xgafv=None)</code>
   <pre>Removes the specified project resource identified by a tenant resource tag.
 The method removes the project lien with 'TenantManager' origin if that
 was added. It then attempts to delete the project. If that operation
@@ -723,12 +727,12 @@
 Calls to remove already removed or non-existent tenant project succeed.
 After the project has been deleted, or if was already in a DELETED state,
 resource metadata is permanently removed from the tenancy unit.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   name: string, Name of the tenancy unit.
 Such as 'services/service.googleapis.com/projects/12345/tenancyUnits/abcd'. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request message to remove a tenant project resource from the tenancy unit.
@@ -789,19 +793,19 @@
 </div>
 
 <div class="method">
-    <code class="details" id="undeleteProject">undeleteProject(name, body, x__xgafv=None)</code>
+    <code class="details" id="undeleteProject">undeleteProject(name, body=None, x__xgafv=None)</code>
   <pre>Attempts to undelete a previously deleted tenant project. The project must
 be in a DELETED state.
 There are no guarantees that an undeleted project will be in
 a fully restored and functional state. Call the `ApplyTenantProjectConfig`
 method to update its configuration and then validate all managed service
 resources.
-Operation<response: Empty>.
+Operation&lt;response: Empty&gt;.
 
 Args:
   name: string, Name of the tenancy unit.
 Such as 'services/service.googleapis.com/projects/12345/tenancyUnits/abcd'. (required)
-  body: object, The request body. (required)
+  body: object, The request body.
     The object takes the form of:
 
 { # Request message to undelete tenant project resource previously deleted from