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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 for_host(parent, host):
 """ Returns a new AccountProxy that has an account acquired. The account is chosen based on what the connected AccountManager selects for the given host. """

        account = AccountProxy(parent)
        account.host = host
        if account.acquire():
            return account
        return None