adds binary check

amazon/ionbenchmark/ion_benchmark_cli.py

@@ -384,7 +384,7 @@ def write_micro_benchmark_simpleion(iterations, warmups, c_extension, file, bina
 # Benchmarks JSON/CBOR dump/dumps APIs
 def write_micro_benchmark(iterations, warmups, c_extension, file, binary, memory_profiling, format_option, io_type):
     file_size = Path(file).stat().st_size / BYTES_TO_MB
-    obj = generate_json_and_cbor_obj_for_write(file, format_option)
+    obj = generate_json_and_cbor_obj_for_write(file, format_option, binary=binary)
     # GC refers to reference cycles, not reference count
     setup_with_gc = generate_setup(format_option=format_option, gc=False, memory_profiling=memory_profiling)
 
@@ -555,8 +555,8 @@ def reset_for_each_execution(each_option):
     return api, format_option, io_type
 
 
-def generate_json_and_cbor_obj_for_write(file, format_option):
-    with open(file) as fp:
+def generate_json_and_cbor_obj_for_write(file, format_option, binary):
+    with open(file, 'br' if binary else 'r') as fp:
         if format_option == Format.JSON.value:
             return json.load(fp)
         elif format_option == Format.SIMPLEJSON.value: