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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def column_creation_ddl(sqla_column: Column, dialect: Dialect) -> str: """ Returns DDL to create a column, using the specified dialect. The column should already be bound to a table (because e.g. the SQL Server dialect requires this for DDL generation). Manual testing: .. code-block:: python from sqlalchemy.schema import Column, CreateColumn, MetaData, Sequence, Table from sqlalchemy.sql.sqltypes import BigInteger from sqlalchemy.dialects.mssql.base import MSDialect dialect = MSDialect() col1 = Column('hello', BigInteger, nullable=True) col2 = Column('world', BigInteger, autoincrement=True) # does NOT generate IDENTITY col3 = Column('you', BigInteger, Sequence('dummy_name', start=1, increment=1)) metadata = MetaData() t = Table('mytable', metadata) t.append_column(col1) t.append_column(col2) t.append_column(col3) print(str(CreateColumn(col1).compile(dialect=dialect))) # hello BIGINT NULL print(str(CreateColumn(col2).compile(dialect=dialect))) # world BIGINT NULL print(str(CreateColumn(col3).compile(dialect=dialect))) # you BIGINT NOT NULL IDENTITY(1,1) If you don't append the column to a Table object, the DDL generation step gives: .. code-block:: none sqlalchemy.exc.CompileError: mssql requires Table-bound columns in order to generate DDL """
  # noqa
    return str(CreateColumn(sqla_column).compile(dialect=dialect))