'Create a copy of this ``Column``, unitialized.
This is used in ``Table.tometadata``.'

def copy(self, **kw):

    args = ([c.copy(**kw) for c in self.constraints] + [c.copy(**kw) for c in self.foreign_keys if (not c.constraint)])
    type_ = self.type
    if isinstance(type_, SchemaEventTarget):
        type_ = type_.copy(**kw)
    c = self._constructor(name=self.name, type_=type_, key=self.key, primary_key=self.primary_key, nullable=self.nullable, unique=self.unique, system=self.system, index=self.index, autoincrement=self.autoincrement, default=self.default, server_default=self.server_default, onupdate=self.onupdate, server_onupdate=self.server_onupdate, doc=self.doc, *args)
    return self._schema_item_copy(c)
