old_contents: # Copyright 2019-present Kensho Technologies, LLC.
  from ..exceptions import MissingPrimaryKeyError
  
  
  def validate_that_tables_have_primary_keys(tables):
      """Validate that each SQLAlchemy Table object has a primary key."""
      for table in tables:
          if not table.primary_key:
              raise MissingPrimaryKeyError(
                  "SQLAlchemy Table with name {} and schema {} is missing a "
                  "primary key. Note that the primary keys in SQLAlchemy "
                  "Table objects do not have to match the primary keys in"
                  "the underlying row. They must simple be unique and "
                  "non-null identifiers of each row.".format(table.name, table.schema)
              )
  
  
  def validate_that_tables_belong_to_the_same_metadata_object(tables):
      """Validate that all the SQLAlchemy Table objects belong to the same MetaData object."""
      metadata = None
      for table in tables:
          if metadata is None:
              metadata = table.metadata
          else:
              if table.metadata is not metadata:
                  raise AssertionError(
                      "Multiple SQLAlchemy MetaData objects used for schema " "generation."
                  )
  
new_contents: # Copyright 2019-present Kensho Technologies, LLC.
  from ..exceptions import MissingPrimaryKeyError
  
  
  def validate_that_tables_have_primary_keys(tables):
      """Validate that each SQLAlchemy Table object has a primary key."""
      for table in tables:
          if not table.primary_key:
              raise MissingPrimaryKeyError(
                  "SQLAlchemy Table with name {} and schema {} is missing a "
                  "primary key. Note that the primary keys in SQLAlchemy "
                  "Table objects do not have to match the primary keys in "
                  "the underlying row. They must simple be unique and "
                  "non-null identifiers of each row.".format(table.name, table.schema)
              )
  
  
  def validate_that_tables_belong_to_the_same_metadata_object(tables):
      """Validate that all the SQLAlchemy Table objects belong to the same MetaData object."""
      metadata = None
      for table in tables:
          if metadata is None:
              metadata = table.metadata
          else:
              if table.metadata is not metadata:
                  raise AssertionError(
                      "Multiple SQLAlchemy MetaData objects used for schema " "generation."
                  )
  
subject: Fix typo (#756)