def deploy_tokens_and_fund_accounts(
    token_amount: int,
    number_of_tokens: int,
    deploy_service: BlockChainService,
    participants: typing.List[typing.Address],
    contract_manager: ContractManager,
) -> typing.List[typing.TokenAddress]:
    """ Deploy `number_of_tokens` ERC20 token instances with `token_amount` minted and
    distributed among `blockchain_services`. Optionally the instances will be registered with
    the raiden registry.

    Args:
        token_amount (int): number of units that will be created per token
        number_of_tokens (int): number of token instances that will be created
        deploy_service (BlockChainService): the blockchain connection that will deploy
        participants (list(address)): participant addresses that will receive tokens
    """
    result = list()
    for _ in range(number_of_tokens):
        token_address = deploy_contract_web3(
            CONTRACT_HUMAN_STANDARD_TOKEN,
            deploy_service.client,
            contract_manager=contract_manager,
            constructor_arguments=(token_amount, 2, "raiden", "Rd"),
        )

        result.append(token_address)

        # only the creator of the token starts with a balance (deploy_service),
        # transfer from the creator to the other nodes
        for transfer_to in participants:
            deploy_service.token(token_address).transfer(
                to_address=transfer_to, amount=token_amount // len(participants)
            )

    return result
def patch_migrate():
    """A workaround for SQLite's inability to alter things

    SQLite abilities to alter tables are very limited (please read
    http://www.sqlite.org/lang_altertable.html for more details).
    E. g. one can't drop a column or a constraint in SQLite. The
    workaround for this is to recreate the original table omitting
    the corresponding constraint (or column).

    sqlalchemy-migrate library has recreate_table() method that
    implements this workaround, but it does it wrong:

        - information about unique constraints of a table
          is not retrieved. So if you have a table with one
          unique constraint and a migration adding another one
          you will end up with a table that has only the
          latter unique constraint, and the former will be lost

        - dropping of unique constraints is not supported at all

    The proper way to fix this is to provide a pull-request to
    sqlalchemy-migrate, but the project seems to be dead. So we
    can go on with monkey-patching of the lib at least for now.

    """

    # this patch is needed to ensure that recreate_table() doesn't drop
    # existing unique constraints of the table when creating a new one
    helper_cls = sqlite.SQLiteHelper
    helper_cls.recreate_table = _recreate_table
    helper_cls._get_unique_constraints = _get_unique_constraints

    # this patch is needed to be able to drop existing unique constraints
    constraint_cls = sqlite.SQLiteConstraintDropper
    constraint_cls.visit_migrate_unique_constraint = \
        _visit_migrate_unique_constraint
    constraint_cls.__bases__ = (ansisql.ANSIColumnDropper,
                                sqlite.SQLiteConstraintGenerator)