data = b64decode(param).decode("ascii")
        except (ValueError, UnicodeDecodeError, binascii.Error):
            raise invalid_user_credentials_exc  # noqa: B904
        username, separator, password = data.partition(":")
        if not separator:
            raise invalid_user_credentials_exc
        return HTTPBasicCredentials(username=username, password=password)


class HTTPBearer(HTTPBase):
    """