title: Insert a new line or an empty line between two sentences
body: <p>i have a text file as the output of another program. I want to insert a white space above the line that starts with 'Sentence #'</p>
  
  <p>this is what i currently have: </p>
  
  <pre><code>Sentence #26024 (5 tokens):
  Today is a good day
  [Text=Today CharacterOffsetBegin=1607176 CharacterOffsetEnd=1607178 PartOfSpeech=IN Lemma=if]
  [Text=is CharacterOffsetBegin=1607179 CharacterOffsetEnd=1607181 
  PartOfSpeech=NN Lemma=yo]
  [Text=a CharacterOffsetBegin=1607182 CharacterOffsetEnd=1607186 PartOfSpeech=NN Lemma=girl]
  [Text=good CharacterOffsetBegin=1607187 CharacterOffsetEnd=1607193 PartOfSpeech=JJ Lemma=doesnt]
  [Text=day CharacterOffsetBegin=1607202 CharacterOffsetEnd=1607205 
  root(ROOT-0, today-1)
  root(today-1, is-2)
  dobj(a-2, good-3)
  amod(day-3, good-4)
  Sentence #26025 (4 tokens):
  if you can help 
  [Text=if CharacterOffsetBegin=1607223 CharacterOffsetEnd=1607225 PartOfSpeech=IN Lemma=if]
  [Text=you CharacterOffsetBegin=1607226 CharacterOffsetEnd=1607229 PartOfSpeech=PRP Lemma=you]
  [Text=can CharacterOffsetBegin=1607230 CharacterOffsetEnd=1607233 PartOfSpeech=MD Lemma=can
  mark(help-4, if-1)
  nsubj(help-4, you-2)
  aux(help-4, can-3)
  </code></pre>
  
  <p>This is what i want it to look like: </p>
  
  <pre><code>Sentence #26024 (5 tokens):
  Today is a good day
  [Text=Today CharacterOffsetBegin=1607176 CharacterOffsetEnd=1607178 PartOfSpeech=IN Lemma=if]
  [Text=is CharacterOffsetBegin=1607179 CharacterOffsetEnd=1607181 
  PartOfSpeech=NN Lemma=yo]
  [Text=a CharacterOffsetBegin=1607182 CharacterOffsetEnd=1607186 PartOfSpeech=NN Lemma=girl]
  [Text=good CharacterOffsetBegin=1607187 CharacterOffsetEnd=1607193 PartOfSpeech=JJ Lemma=doesnt]
  [Text=day CharacterOffsetBegin=1607202 CharacterOffsetEnd=1607205 
  root(ROOT-0, today-1)
  root(today-1, is-2)
  dobj(a-2, good-3)
  amod(day-3, good-4)
  
  Sentence #26025 (4 tokens):
  if you can help 
  [Text=if CharacterOffsetBegin=1607223 CharacterOffsetEnd=1607225 PartOfSpeech=IN Lemma=if]
  [Text=you CharacterOffsetBegin=1607226 CharacterOffsetEnd=1607229 PartOfSpeech=PRP Lemma=you]
  [Text=can CharacterOffsetBegin=1607230 CharacterOffsetEnd=1607233 PartOfSpeech=MD Lemma=can
  mark(help-4, if-1)
  nsubj(help-4, you-2)
  aux(help-4, can-3)
  </code></pre>
  
  <p>Can anyone please provide pointers. Thanks</p>
  
  <p>I can't do it manually because it's a large file that will need thoussand of spaces inserted. </p>