def METHOD_NAME(access_token_response: str) -> AccessCredentials:
    """
    The Access token response contains both the Proton Session ID and the Access Token.
    The Session ID is necessary in order to use the Proton API. However, the OAuth response does not allow us to return
    extra content.
    This method takes the Access token response and extracts the session ID and the access token.
    """
    parts = access_token_response.split("-")
    if len(parts) != 3:
        raise Exception("Invalid access token response")
    if parts[0] != "pt":
        raise Exception("Invalid access token response format")
    return AccessCredentials(
        session_id=parts[1],
        access_token=parts[2],
    )