By Claire Coleman For the past four years, 24-year-old engineering student Sofia Ahmed has been leading a double life. During a typical week, she will study in her university library by day, then head to any one of Liverpool’s many student bars at night. There, she will party until the early hours: drinking, smoking and experimenting with the hedonistic lifestyle of a typical British undergraduate. But at the weekend, Sofia plays the role of a completely different person; a dutiful