Given the task definition and input, reply with output. In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: By September 1963, Waters and Mason had lost interest in their studies and moved into the lower flat of Stanhope Gardens, owned by Mike Leonard, a part-time tutor at the Regent Street Polytechnic. Waters, Mason and Wright first played music together in late 1963, in a band formed by vocalist Keith Noble and bassist Clive Metcalfe. They usually called themselves Sigma 6, but also used the name the Meggadeaths. Waters played rhythm guitar and Mason played drums, Wright played any keyboard he could arrange to use, and Noble's sister Sheilagh provided occasional vocals. In the early years the band performed during private functions and rehearsed in a tearoom in the basement of Regent Street Polytechnic.When Metcalfe and Noble left to form their own group in September 1963, the remaining members asked Barrett and guitarist Bob Klose to join. Waters switched to the bass and by January 1964, the group became known as the Abdabs, or the Screaming Abdabs. During late 1964, the band used the names Leonard's Lodgers, Spectrum Five, and eventually, the Tea Set. Sometime during late 1965, the Tea Set began calling itself the Pink Floyd Sound, later the Pink Floyd Blues Band and by early 1966, Pink Floyd.By early 1966, Barrett was Pink Floyd's frontman, guitarist, and songwriter. He wrote or co-wrote all but one track of their debut LP The Piper at the Gates of Dawn, released in August 1967. Waters contributed the song "Take Up Thy Stethoscope and Walk" (his first sole writing credit) to the album. By late 1967, Barrett's deteriorating mental health and increasingly erratic behaviour, rendered him "unable or unwilling" to continue in his capacity as Pink Floyd's singer-songwriter and lead guitarist. In early March 1968 Pink Floyd met with managers Peter Jenner and Andrew King of Blackhill Enterprises to discuss the band's future. Barrett agreed to leave Pink Floyd, and the band "agreed to Blackhill's entitlement in perpetuity" regarding "past activities". The band's new manager Steve O'Rourke made a formal announcement about the departure of Barrett and the arrival of David Gilmour in April 1968.
What is the name of the person who wrote or co-wrote all but one track of the debut LP The Piper at the Gates of Dawn, released in August 1967?