System: As an API testing assistant, analyze API specifications and previous test results to generate new, unused parameters. Avoid using any parameters from the previous attempts. Return only the parameter dictionary.
User: API Specification:
URL: https://qr-code-by-api-ninjas.p.rapidapi.com/v1/qrcode
Method: GET
Required Parameters: [{'name': 'data', 'type': 'STRING', 'description': 'Data to encode in the QR code.', 'default': 'https://api-ninjas.com'}, {'name': 'format', 'type': 'STRING', 'description': 'Image format to return. Must be one of the following: png, jpg, jpeg, eps, svg.', 'default': 'png'}]
Optional Parameters: [{'name': 'size', 'type': 'NUMBER', 'description': 'Size of the QR code image to generate. The output will be a square image with (size x size) dimensions.', 'default': ''}, {'name': 'fg_color', 'type': 'STRING', 'description': 'Foreground color of the QR code. Must be a 6-digit hex color (e.g. 00ff00 for green). Default is 000000 (black).', 'default': ''}, {'name': 'bg_color', 'type': 'STRING', 'description': 'Background color of the QR code. Must be a 6-digit hex color (e.g. 00ff00 for green). Default is ffffff (white).', 'default': ''}]
Previous attempts: Initial Attempt 1:
Parameters: {'data': 'https://example.com', 'format': 'jpg', 'size': 300, 'fg_color': 'ff5733', 'bg_color': 'ffffff'}
Result: Failed
Analysis: Failed - possible issues: API returned error: Expecting value: line 1 column 1 (char 0)

Initial Attempt 2:
Parameters: {'data': 'https://new-example.com', 'format': 'svg', 'size': 250, 'fg_color': '00ff00', 'bg_color': '0000ff'}
Result: Failed
Analysis: Failed - possible issues: API returned error: Expecting value: line 1 column 1 (char 0)

Recent Attempt 3:
Parameters: {'data': 'https://api-ninjas.com', 'format': 'jpeg', 'size': 400, 'fg_color': 'ff0000', 'bg_color': '00ff00'}
Result: Failed
Analysis: Failed - possible issues: API returned error: Expecting value: line 1 column 1 (char 0)

Recent Attempt 4:
Parameters: {'data': 'https://unique-example.com', 'format': 'eps', 'size': 350, 'fg_color': '123456', 'bg_color': 'abcdef'}
Result: Failed
Analysis: Failed - possible issues: API returned error: Expecting value: line 1 column 1 (char 0)

Recent Attempt 5:
Parameters: {'data': 'https://new-unique-example.com', 'format': 'png', 'size': 150, 'fg_color': 'ffcc00', 'bg_color': '000000'}
Result: Failed
Analysis: Failed - possible issues: API returned error: Expecting value: line 1 column 1 (char 0)

Already used parameters: - {'bg_color': '00ff00', 'data': 'https://api-ninjas.com', 'fg_color': 'ff0000', 'format': 'jpeg', 'size': '400'}
- {'bg_color': '000000', 'data': 'https://new-unique-example.com', 'fg_color': 'ffcc00', 'format': 'png', 'size': '150'}
- {'bg_color': '0000ff', 'data': 'https://new-example.com', 'fg_color': '00ff00', 'format': 'svg', 'size': '250'}
- {'bg_color': 'ffcc00', 'data': 'https://another-example.com', 'fg_color': '000000', 'format': 'png', 'size': '200'}
- {'bg_color': 'ffffff', 'data': 'https://example.com', 'fg_color': 'ff5733', 'format': 'jpg', 'size': '300'}
- {'bg_color': 'abcdef', 'data': 'https://unique-example.com', 'fg_color': '123456', 'format': 'eps', 'size': '350'}

Rules:
1. If required_parameters is empty and you choose not to use optional parameters, return empty dict.
2. If using optional parameters, only use parameters exactly as defined in optional_parameters.
3. Do not create new parameters that are not in the specification.

Generate valid parameters:
Assistant: