import re
rx = re.compile(r'''[][!":$()',]|(\d+)''')
sentence = ['cracked $300 million','she\'s resolutely, smitten ', 'that\'s creative [r]', 'the market ( knowledge check : prices up!']
s = [rx.sub(lambda x: '£' if x.group(1) else ' ', word) for word in sentence]
print(s)
aW1wb3J0IHJlCnJ4ID0gcmUuY29tcGlsZShyJycnW11bISI6JCgpJyxdfChcZCspJycnKQpzZW50ZW5jZSA9IFsnY3JhY2tlZCAkMzAwIG1pbGxpb24nLCdzaGVcJ3MgcmVzb2x1dGVseSwgc21pdHRlbiAnLCAndGhhdFwncyBjcmVhdGl2ZSBbcl0nLCAndGhlIG1hcmtldCAoIGtub3dsZWRnZSBjaGVjayA6IHByaWNlcyB1cCEnXQpzID0gW3J4LnN1YihsYW1iZGEgeDogJ8KjJyBpZiB4Lmdyb3VwKDEpIGVsc2UgJyAnLCB3b3JkKSBmb3Igd29yZCBpbiBzZW50ZW5jZV0gCnByaW50KHMpCg==