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I don't really have a lot of feedback on your code other than it feels awkward with things like

1. side effect next(b, None) in pairwise
2. starmap instead of list comprehension in pascal

They're not wrong but they just feel out of place to me. Here's how I might write your pascal program

def sliding (n,xs):
 if n > len(xs):
 return []
 else:
 return [xs[0:n]] + sliding(n, xs[1:])
 
def pascal (n):
 def loop (m, prev, k):
 if n == m:
 return k([prev])
 else:
 return loop(m + 1, [1] + [x + y for (x,y) in sliding(2, prev)] + [1], lambda rest: k([prev] + rest))
 return loop(1, [1], lambda x: x)
 
def print_pascal (n):
 [print(line) for line in pascal(n)]
print_pascal(10)
# [1]
# [1, 1]
# [1, 2, 1]
# [1, 3, 3, 1]
# [1, 4, 6, 4, 1]
# [1, 5, 10, 10, 5, 1]
# [1, 6, 15, 20, 15, 6, 1]
# [1, 7, 21, 35, 35, 21, 7, 1]
# [1, 8, 28, 56, 70, 56, 28, 8, 1]
# [1, 9, 36, 84, 126, 126, 84, 36, 9, 1]

Or maybe just leave it define in continuation passing style

def sliding (n,xs):
 if n > len(xs):
 return []
 else:
 return [xs[0:n]] + sliding(n, xs[1:])
 
def pascalk (n,k):
 def loop (m, prev, k):
 if n == m:
 return k([prev])
 else:
 return loop(m + 1, [1] + [x + y for (x,y) in sliding(2, prev)] + [1], lambda rest: k([prev] + rest))
 return loop(1, [1], k)
pascalk(10, lambda rows: [print(row) for row in rows])
# [1]
# [1, 1]
# [1, 2, 1]
# [1, 3, 3, 1]
# [1, 4, 6, 4, 1]
# [1, 5, 10, 10, 5, 1]
# [1, 6, 15, 20, 15, 6, 1]
# [1, 7, 21, 35, 35, 21, 7, 1]
# [1, 8, 28, 56, 70, 56, 28, 8, 1]
# [1, 9, 36, 84, 126, 126, 84, 36, 9, 1]