Dummy bug in my Python programming

My buggy program:

for line in fin.open('onefile'):
list = line.strip().split('\t')
... (other goodies)

def revComplimentary(seq):
li = list(seq)
... (other goodies)

When the self-defined function is called, a TypeError is thrown saying "list object is not callable". What hell is this problem? It turns out that I have redefined "list" to be an object in file processing.