我正在学习集体智能的工作原理，并且正在练习第 2 章中的示例 Recommendations.py 问题。这是链接：
http://cdn.jampad.net/Library/collectiveintelligence/#calibre_link-201
当我复制并粘贴此代码时：
# Gets recommendations for a person by using a weighted average
# of every other user's rankings
def getRecommendations(prefs,person,similarity=sim_pearson):
totals={}
simSums={}
for other in prefs:
# don't compare me to myself
if other==person: continue
sim=similarity(prefs,person,other)
# ignore scores of zero or lower
if sim<=0: continue
for item in prefs[other]:
# only score movies I haven't seen yet
if item not in prefs[person] or prefs[person][item]==0:
# Similarity * Score
totals.setdefault(item,0)totals[item]+=prefs[other][item]*sim
# Sum of similarities
simSums.setdefault(item,0)
simSums[item]+=sim
# Create the normalized list
rankings=[(total/simSums[item],item) for item,total in totals.items( )]
# Return the sorted list
rankings.sort( )
rankings.reverse( )
return rankings
进入我的 Recommendations.py 文件，当我重新加载文件时，我收到一个语法错误。
>>> reload(recommendations)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "recommendations.py", line 100
totals.setdefault(item,0)totals[item]+=prefs[other][item]*sim
^
SyntaxError: invalid syntax
这就是我收到的信息。我不确定我是否正确复制并粘贴了代码，或者给定的代码行是否错误。