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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 _get_file_stream(self, total_content_length, content_type, filename=None, content_length=None):
 """Called to get a stream for the file upload. This must provide a file-like class with `read()`, `readline()` and `seek()` methods that is both writeable and readable. The default implementation returns a temporary file if the total content length is higher than 500KB. Because many browsers do not provide a content length for the files only the total content length matters. :param total_content_length: the total content length of all the data in the request combined. This value is guaranteed to be there. :param content_type: the mimetype of the uploaded file. :param filename: the filename of the uploaded file. May be `None`. :param content_length: the length of this file. This value is usually not provided because webbrowsers do not provide this value. """

        return default_stream_factory(total_content_length, content_type,
                                      filename, content_length)