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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 ToJsonString(self):
 """Converts FieldMask to string according to proto3 JSON spec."""

    camelcase_paths = []
    for path in self.paths:
      camelcase_paths.append(_SnakeCaseToCamelCase(path))
    return ','.join(camelcase_paths)