Need advice on reading contents of a file into memory

[vinjvinj]

f = open(someFilePath, "rb")
content = []
for data in content.read()
   content.append(data)
fullContent = "".join(content)

Is there a more efficient way of doing this? I'll be running this
operation on 10,000+ files where each file is an image file with size
50k-100k