fix indentation error

app.py

@@ -188,30 +188,29 @@ def is_complex_sentence(sentence):
         return False
 
 def get_complex_sentences(elements):
-
-   complex_sentences = []
-
-  for key, value in elements.items():
-      for i in range(0, len(elements[key])):
-          if is_complex_sentence(elements[key][i]):
-              complex_sentences.append(elements[key][i])
-
-  if complex_sentences:
-    output = ""
-    for complex_sentence in complex_sentences:
-      refactored_element = prompt(
-        '''
-        You are a specialist in English linguistics.
-        A complex sentence is a sentence with one independent clause and at least one dependent clause. A simple sentence has a single independent clause.
-        You will be provided with a complex sentence, and your task is to make it a simple sentence.
-        Do not convert a verb phrase to a noun phrase, and vice versa.
-        Answer with the new sentence only.
-        ''', complex_sentence)
-      output = output + '"' + complex_sentence + '" should be refactored to "' + refactored_element + '"\n'
-    #complex_sentences = "\n".join(complex_sentences)
-    return "Complex elements:\n" + output
-  else:
-    return ""
+    
+    complex_sentences = []
+
+    for key, value in elements.items():
+        for i in range(0, len(elements[key])):
+            if is_complex_sentence(elements[key][i]):
+                complex_sentences.append(elements[key][i])
+
+    if complex_sentences:
+        output = ""
+        for complex_sentence in complex_sentences:
+            refactored_element = prompt(
+            '''
+            You are a specialist in English linguistics.
+            A complex sentence is a sentence with one independent clause and at least one dependent clause. A simple sentence has a single independent clause.
+            You will be provided with a complex sentence, and your task is to make it a simple sentence.
+            Do not convert a verb phrase to a noun phrase, and vice versa.
+            Answer with the new sentence only.
+            ''', complex_sentence)
+            output = output + '"' + complex_sentence + '" should be refactored to "' + refactored_element + '"\n'
+        return "Complex elements:\n" + output
+    else:
+        return ""
 
 # #####################################