def add_field(self, model, field):
        # Special-case implicit M2M tables
        if field.many_to_many and field.remote_field.through._meta.auto_created:
            return self.create_model(field.remote_field.through)
        # Get the column's definition
        definition, params = self.column_sql(model, field, include_default=True)
        # It might not actually have a column behind it
        if definition is None:
            return
        # Check constraints can go on the column SQL here
        db_params = field.db_parameters(connection=self.connection)
        if db_params['check']:
            definition += " CHECK (%s)" % db_params['check']
        # Build the SQL and run it
        sql = self.sql_create_column % {
            "table": self.quote_name(model._meta.db_table),
            "column": self.quote_name(field.column),
            "definition": definition,
        }
        self.execute(sql, params)
        # Drop the default if we need to
        # (Django usually does not use in-database defaults)
        if not self.skip_default(field) and field.default is not None:
            sql = self.sql_alter_column % {
                "table": self.quote_name(model._meta.db_table),
                "changes": self.sql_alter_column_no_default % {
                    "column": self.quote_name(field.column),
                }
            }
            self.execute(sql)
        # Add an index, if required
        if field.db_index and not field.unique:
            self.deferred_sql.append(self._create_index_sql(model, [field]))
        # Add any FK constraints later
        if field.remote_field and self.connection.features.supports_foreign_keys and field.db_constraint:
            self.deferred_sql.append(self._create_fk_sql(model, field, "_fk_%(to_table)s_%(to_column)s"))
        # Reset connection if required
        if self.connection.features.connection_persists_old_columns:
            self.connection.close()
>>> c = C()
dataset/ETHPy150Open django/django/django/db/backends/base/schema.py/BaseDatabaseSchemaEditor.add_field--crossover with--dataset/ETHPy150Open kuri65536/python-for-android/python-modules/zope/zope/interface/tests/test_declarations.py/test_ObjectSpecification_Simple