graph TD %% External Entities Student[Student] %% Process 2.0 Decomposition P21[2.1 User Authentication] P22[2.2 Retrieve Borrowed Books] P23[2.3 Generate Chatbot Content] P24[2.4 Calculate Deadlines] P25[2.5 Send Notifications] %% Data Stores D1[(D1 Student Database)] D2[(D2 Book Inventory)] D3[(D3 Transaction Records)] D4[(D4 System Configuration)] %% External Entity Connections Student --> |"Login Credentials"| P21 P22 --> |"Borrowed Books List"| Student P23 --> |"Genre-based Chatbot Content"| Student P25 --> |"Due Date Notifications"| Student %% Process Flow P21 --> |"Credential Verification"| D1 P21 --> |"Authenticated Session"| P22 P22 --> |"Transaction Query"| D3 P22 --> |"Book Details Request"| P24 P23 --> |"Book Genre Data"| D2 P23 --> |"Student Preferences"| D1 P24 --> |"Deadline Configuration"| D4 P24 --> |"Due Date Calculations"| P25