code: def pre_migration(verbose):
      for _ in range(5):
          log_everything()
      SNAPSHOTS_DIR.mkdir(exist_ok=True)
      with connect_to_mlflow_db() as conn:
          for table in TABLES:
              df = pd.read_sql(sa.text(f"SELECT * FROM {table}"), conn)
              df.to_pickle(SNAPSHOTS_DIR / f"{table}.pkl")
              if verbose:
                  click.secho(f"\n{table}\n", fg="blue")
                  click.secho(df.head(5).to_markdown(index=False))
  
file_path: mlflow/tests/db/check_migration.py
imports: import os
  import uuid
  from pathlib import Path
  import click
  import pandas
  import sqlalchemy
  import mlflow
  from mlflow.store.model_registry.dbmodels.models import SqlModelVersion, SqlModelVersionTag, SqlRegisteredModel, SqlRegisteredModelTag
  from mlflow.store.tracking.dbmodels.models import SqlExperiment, SqlExperimentTag, SqlLatestMetric, SqlMetric, SqlParam, SqlRun, SqlTag
label_desc: Use image node_id 4 for calling a global function with example usage: pre_migration(verbose) without return types