从以下的Google Cloud Storage模拟开始
```python
from google.cloud import storage
class MockBlob:
    def download_as_string(self) -> bytes:
        return bytes("\n".join(INPUT_IDS), "utf-8")
class MockBucket:
    def get_blob(self, path: str) -> MockBlob:
        return MockBlob()
class MockStorageClient(storage.Client):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
    def _require_client_info(self, client_info=None):
        pass
    def _require_virtual(self):
        pass
    def get_bucket(self, bucket_or_name: str):
        return MockBucket()

.venv/lib/python3.8/site-packages/google/cloud/storage/client.py:173: in __init__
    super(Client, self).__init__(
.venv/lib/python3.8/site-packages/google/cloud/client/__init__.py:320: in __init__
    _ClientProjectMixin.__init__(self, project=project, credentials=credentials)
.venv/lib/python3.8/site-packages/google/cloud/client/__init__.py:268: in __init__
    project = self._determine_default(project)
.venv/lib/python3.8/site-packages/google/cloud/client/__init__.py:287: in _determine_default
    return _determine_default_project(project)
.venv/lib/python3.8/site-packages/google/cloud/_helpers/__init__.py:152: in _determine_default_project
    _, project = google.auth.default()
.venv/lib/python3.8/site-packages/google/auth/_default.py:615: in default
    credentials, project_id = checker()
.venv/lib/python3.8/site-packages/google/auth/_default.py:608: in <lambda>
    lambda: _get_explicit_environ_credentials(quota_project_id=quota_project_id),
.venv/lib/python3.8/site-packages/google/auth/_default.py:228: in _get_explicit_environ_credentials
    credentials, project_id = load_credentials_from_file(
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
filename = '', scopes = None, default_scopes = None, quota_project_id = None, request = None
    def load_credentials_from_file(
        filename, scopes=None, default_scopes=None, quota_project_id=None, request=None
    ):
        """Loads Google credentials from a file.
    
        The credentials file must be a service account key, stored authorized
        user credentials, external account credentials, or impersonated service
        account credentials.
    
        Args:
            filename (str): The full path to the credentials file.
            scopes (Optional[Sequence[str]]): The list of scopes for the credentials. If
                specified, the credentials will automatically be scoped if
                necessary
            default_scopes (Optional[Sequence[str]]): Default scopes passed by a
                Google client library. Use 'scopes' for user-defined scopes.
            quota_project_id (Optional[str]):  The project ID used for
                quota and billing.
            request (Optional[google.auth.transport.Request]): An object used to make
                HTTP requests. This is used to determine the associated project ID
                for a workload identity pool resource (external account credentials).
                If not specified, then it will use a
                google.auth.transport.requests.Request client to make requests.
    
        Returns:
            Tuple[google.auth.credentials.Credentials, Optional[str]]: Loaded
                credentials and the project ID. Authorized user credentials do not
                have the project ID information. External account credentials project
                IDs may not always be determined.
    
        Raises:
            google.auth.exceptions.DefaultCredentialsError: if the file is in the
                wrong format or is missing.
        """
        if not os.path.exists(filename):
>           raise exceptions.DefaultCredentialsError(
                "File {} was not found.".format(filename)
            )
E           google.auth.exceptions.DefaultCredentialsError: File  was not found.
.venv/lib/python3.8/site-packages/google/auth/_default.py:116: DefaultCredentialsError

您可以简单地覆盖失败的函数，如下所示：
```python
from google.auth import credentials
import google.auth._default
def load_credentials_from_file(
    filename, scopes=None, default_scopes=None, quota_project_id=None, request=None
) -> Tuple[credentials.Credentials, Optional[str]]:
    return (credentials.AnonymousCredentials(), "test-project")
google.auth._default.load_credentials_from_file = load_credentials_from_file

<details>
<summary>英文:</summary>
You can simply override the function that fails as 
```python
from google.auth import credentials
import google.auth._default
def load_credentials_from_file(
filename, scopes=None, default_scopes=None, quota_project_id=None, request=None
) -&gt; Tuple[credentials.Credentials, Optional[str]]:
return (credentials.AnonymousCredentials(), &quot;test-project&quot;)
google.auth._default.load_credentials_from_file = load_credentials_from_file