Analyze the sentiment expressed in the tweet. Is it positive, negative, or neutral? Explain the sentiment in relation to the stock mentioned.
TWEET: "RT @IBM: #TBT: In 1977, IBM developed the world's first mutually agreed-upon cryptographic algorithm to secure data 🔐. In 20… 
" STOCK: IBM DATE: 01/12/2017
Sentiment: (Provide sentiment here)
Explanation: The tweet sentiment is related to the stock mentioned, and it's important to interpret the context. The LSTM polarity score is -1 and the TextBlob polarity score is 0.25.