| 12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849 | """conversation columns set nullableRevision ID: 42e85ed5564dRevises: f9107f83ababCreate Date: 2024-03-07 08:30:29.133614"""import sqlalchemy as safrom alembic import opfrom sqlalchemy.dialects import postgresql# revision identifiers, used by Alembic.revision = '42e85ed5564d'down_revision = 'f9107f83abab'branch_labels = Nonedepends_on = Nonedef upgrade():    # ### commands auto generated by Alembic - please adjust! ###    with op.batch_alter_table('conversations', schema=None) as batch_op:        batch_op.alter_column('app_model_config_id',                              existing_type=postgresql.UUID(),                              nullable=True)        batch_op.alter_column('model_provider',                              existing_type=sa.VARCHAR(length=255),                              nullable=True)        batch_op.alter_column('model_id',                              existing_type=sa.VARCHAR(length=255),                              nullable=True)    # ### end Alembic commands ###def downgrade():    # ### commands auto generated by Alembic - please adjust! ###    with op.batch_alter_table('conversations', schema=None) as batch_op:        batch_op.alter_column('model_id',                              existing_type=sa.VARCHAR(length=255),                              nullable=False)        batch_op.alter_column('model_provider',                              existing_type=sa.VARCHAR(length=255),                              nullable=False)        batch_op.alter_column('app_model_config_id',                              existing_type=postgresql.UUID(),                              nullable=False)    # ### end Alembic commands ###
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