diff --git a/src/cli.py b/src/cli.py
index 2c0bc37..2d7cc93 100644
--- a/src/cli.py
+++ b/src/cli.py
@@ -16,13 +16,15 @@ def main():
 @click.option('--num_approaches', default=3, type=int,
               help='Number of num_approaches to use to fulfill the task (default: 3).')
 @click.option('--output_path', default='executor', help='Path to the output folder (must be empty). ')
+@click.option('--model', default='gpt-4', help='GPT model to use (default: gpt-4).')
 def create(
         description,
         test,
         num_approaches=3,
         output_path='executor',
+        model='gpt-4'
 ):
-    executor_factory = ExecutorFactory()
+    executor_factory = ExecutorFactory(model=model)
     executor_factory.create(description, num_approaches, output_path, test)
 
 
diff --git a/src/executor_factory.py b/src/executor_factory.py
index c7b0a41..ca52766 100644
--- a/src/executor_factory.py
+++ b/src/executor_factory.py
@@ -12,8 +12,8 @@ from src.utils.string_tools import print_colored
 
 
 class ExecutorFactory:
-    def __init__(self):
-        self.gpt_session = gpt.GPTSession()
+    def __init__(self, model='gpt-4'):
+        self.gpt_session = gpt.GPTSession(model=model)
 
     def extract_content_from_result(self, plain_text, file_name):
         pattern = fr"^\*\*{file_name}\*\*\n```(?:\w+\n)?([\s\S]*?)```"
@@ -21,7 +21,13 @@ class ExecutorFactory:
         if match:
             return match.group(1).strip()
         else:
-            return ''
+            # Check for a single code block
+            single_code_block_pattern = r"^```(?:\w+\n)?([\s\S]*?)```"
+            single_code_block_match = re.findall(single_code_block_pattern, plain_text, re.MULTILINE)
+            if len(single_code_block_match) == 1:
+                return single_code_block_match[0].strip()
+            else:
+                return ''
 
     def write_config_yml(self, executor_name, dest_folder):
         config_content = f'''
diff --git a/src/gpt.py b/src/gpt.py
index 7af6da8..c3d0fff 100644
--- a/src/gpt.py
+++ b/src/gpt.py
@@ -11,15 +11,19 @@ from src.prompt_system import system_base_definition
 from src.utils.io import timeout_generator_wrapper, GenerationTimeoutError
 from src.utils.string_tools import print_colored
 
+
 class GPTSession:
-    def __init__(self):
+    def __init__(self, model: str = 'gpt-4'):
         self.get_openai_api_key()
-        if self.is_gpt4_available():
+        if model == 'gpt-4' and self.is_gpt4_available():
             self.supported_model = 'gpt-4'
             self.pricing_prompt = PRICING_GPT4_PROMPT
             self.pricing_generation = PRICING_GPT4_GENERATION
-        else:
-            self.supported_model = 'gpt-3.5-turbo'
+        elif (model == 'gpt-4' and not self.is_gpt4_available()) or model == 'gpt-3.5-turbo':
+            if model == 'gpt-4':
+                print_colored('GPT-4 is not available. Using GPT-3.5-turbo instead.', 'yellow')
+                model = 'gpt-3.5-turbo'
+            self.supported_model = model
             self.pricing_prompt = PRICING_GPT3_5_TURBO_PROMPT
             self.pricing_generation = PRICING_GPT3_5_TURBO_GENERATION
         self.chars_prompt_so_far = 0
@@ -52,8 +56,8 @@ class GPTSession:
         self.chars_prompt_so_far += chars_prompt
         self.chars_generation_so_far += chars_generation
         print('\n')
-        money_prompt = round(self.chars_prompt_so_far / 3.4 * self.pricing_prompt / 1000, 2)
-        money_generation = round(self.chars_generation_so_far / 3.4 * self.pricing_generation / 1000, 2)
+        money_prompt = round(self.chars_prompt_so_far / 3.4 * self.pricing_prompt / 1000, 3)
+        money_generation = round(self.chars_generation_so_far / 3.4 * self.pricing_generation / 1000, 3)
         print('Estimated costs on openai.com:')
         # print('money prompt:', f'${money_prompt}')
         # print('money generation:', f'${money_generation}')