prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  Ensure rotation column == 'False' during migration.
  Null values creates problems during validation.
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `lemur/migrations/versions/131ec6accff5_.py`
  Content:
  ```
  1 """Ensuring we have endpoint updated times and certificate rotation availability.
  2 
  3 Revision ID: 131ec6accff5
  4 Revises: e3691fc396e9
  5 Create Date: 2016-12-07 17:29:42.049986
  6 
  7 """
  8 
  9 # revision identifiers, used by Alembic.
  10 revision = '131ec6accff5'
  11 down_revision = 'e3691fc396e9'
  12 
  13 from alembic import op
  14 import sqlalchemy as sa
  15 
  16 
  17 def upgrade():
  18     # ### commands auto generated by Alembic - please adjust! ###
  19     op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=True))
  20     op.add_column('endpoints', sa.Column('last_updated', sa.DateTime(), server_default=sa.text('now()'), nullable=False))
  21     # ### end Alembic commands ###
  22 
  23 
  24 def downgrade():
  25     # ### commands auto generated by Alembic - please adjust! ###
  26     op.drop_column('endpoints', 'last_updated')
  27     op.drop_column('certificates', 'rotation')
  28     # ### end Alembic commands ###
  29
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/lemur/migrations/versions/131ec6accff5_.py b/lemur/migrations/versions/131ec6accff5_.py
  --- a/lemur/migrations/versions/131ec6accff5_.py
  +++ b/lemur/migrations/versions/131ec6accff5_.py
  @@ -16,7 +16,7 @@
   
   def upgrade():
       # ### commands auto generated by Alembic - please adjust! ###
  -    op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=True))
  +    op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=False, server_default=False))
       op.add_column('endpoints', sa.Column('last_updated', sa.DateTime(), server_default=sa.text('now()'), nullable=False))
       # ### end Alembic commands ###
  
verification_info: {"golden_diff": "diff --git a/lemur/migrations/versions/131ec6accff5_.py b/lemur/migrations/versions/131ec6accff5_.py\n--- a/lemur/migrations/versions/131ec6accff5_.py\n+++ b/lemur/migrations/versions/131ec6accff5_.py\n@@ -16,7 +16,7 @@\n \n def upgrade():\n     # ### commands auto generated by Alembic - please adjust! ###\n-    op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=True))\n+    op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=False, server_default=False))\n     op.add_column('endpoints', sa.Column('last_updated', sa.DateTime(), server_default=sa.text('now()'), nullable=False))\n     # ### end Alembic commands ###\n", "issue": "Ensure rotation column == 'False' during migration.\nNull values creates problems during validation.\n", "before_files": [{"content": "\"\"\"Ensuring we have endpoint updated times and certificate rotation availability.\n\nRevision ID: 131ec6accff5\nRevises: e3691fc396e9\nCreate Date: 2016-12-07 17:29:42.049986\n\n\"\"\"\n\n# revision identifiers, used by Alembic.\nrevision = '131ec6accff5'\ndown_revision = 'e3691fc396e9'\n\nfrom alembic import op\nimport sqlalchemy as sa\n\n\ndef upgrade():\n    # ### commands auto generated by Alembic - please adjust! ###\n    op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=True))\n    op.add_column('endpoints', sa.Column('last_updated', sa.DateTime(), server_default=sa.text('now()'), nullable=False))\n    # ### end Alembic commands ###\n\n\ndef downgrade():\n    # ### commands auto generated by Alembic - please adjust! ###\n    op.drop_column('endpoints', 'last_updated')\n    op.drop_column('certificates', 'rotation')\n    # ### end Alembic commands ###\n", "path": "lemur/migrations/versions/131ec6accff5_.py"}], "after_files": [{"content": "\"\"\"Ensuring we have endpoint updated times and certificate rotation availability.\n\nRevision ID: 131ec6accff5\nRevises: e3691fc396e9\nCreate Date: 2016-12-07 17:29:42.049986\n\n\"\"\"\n\n# revision identifiers, used by Alembic.\nrevision = '131ec6accff5'\ndown_revision = 'e3691fc396e9'\n\nfrom alembic import op\nimport sqlalchemy as sa\n\n\ndef upgrade():\n    # ### commands auto generated by Alembic - please adjust! ###\n    op.add_column('certificates', sa.Column('rotation', sa.Boolean(), nullable=False, server_default=False))\n    op.add_column('endpoints', sa.Column('last_updated', sa.DateTime(), server_default=sa.text('now()'), nullable=False))\n    # ### end Alembic commands ###\n\n\ndef downgrade():\n    # ### commands auto generated by Alembic - please adjust! ###\n    op.drop_column('endpoints', 'last_updated')\n    op.drop_column('certificates', 'rotation')\n    # ### end Alembic commands ###\n", "path": "lemur/migrations/versions/131ec6accff5_.py"}]}