add_metadata Method
Adds a metadata item to the Metadata properties.
Syntax
def add_metadata(name: str, value: str) -> None: ...
Remarks
This method adds a metadata item to the Metadata* properties. Name specifies the name of the item, and Value specifies the value of the item. Keep in mind that the server stores metadata names in lowercase.
If Name begins with a service-specific metadata (e.g., x-amz-meta-, x-goog-meta-, etc.), it will be stripped off. The class will take care of prepending it when sending metadata to the server.