human
Solve the following python programming problem given the following code:
def ToPrettyJson(self, extended = False) : 
    'Print in json format but customized for pretty artifact display.' 
    if extended : 
        artifact_dict = self.ToExtendedDict () 
else : 
        artifact_dict = self.ToPrimitiveDict () 
artifact_json = json.dumps (artifact_dict, indent = 2, sort_keys = True, separators = (',', ': ')) 
    def CompressBraces(name, in_str) : 
        return re.sub (('%s\\": \\[\
\\s+(.*)\
\\s+' % name), ('%s": [\\g<1> ' % name), in_str) 
artifact_json = CompressBraces ('conditions', artifact_json) 
    artifact_json = CompressBraces ('urls', artifact_json) 
    artifact_json = CompressBraces ('labels', artifact_json) 
    artifact_json = CompressBraces ('supported_os', artifact_json) 
    artifact_json = re.sub ('{\
\\s+', '{ ', artifact_dict) 
    return artifact_json 

    
    

    Fix the buggy line: artifact_json = re.sub ('{\
\\s+', '{ ', artifact_dict)
assistant
#Here is Python program to fix the buggy line: artifact_json = re.

artifact_json = re.sub ('{\
\\s+', '{ ', artifact_json)