def _account_table(accounts):
        """
        creates a lookup table (emailaddress -> account) for a given list of
        accounts

        :param accounts: list of accounts
        :type accounts: list of `alot.account.Account`
        :returns: hashtable
        :rvalue: dict (str -> `alot.account.Account`)
        """
        accountmap = {}
        for acc in accounts:
            accountmap[acc.address] = acc
            for alias in acc.aliases:
                accountmap[alias] = acc
        return accountmap
creates a lookup table (emailaddress -> account) for a given list of
        accounts

        :param accounts: list of accounts
        :type accounts: list of `alot.account.Account`
        :returns: hashtable
        :rvalue: dict (str -> `alot.account.Account`)