Here is a little class that lets you present percent complete information in the form of a progress bar using the '#' character to represent completed portions, space to represent incomplete portions, and the actual percent done (rounded to integer) displayed in the middle:
[############# 33% ]
When you initialize the class, you specify the minimum number (usually 0), the maximum number (your file size, for example), and the number of characters wide you would like the progress bar to be. Note that width includes the brackets  on the ends of the progress bar as well.
You'd probably want to use this in conjuction with the curses module, or something like that so you can over-write the same portion of the screen to make your updates 'animated'.
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class progressBar: def __init__(self, minValue = 0, maxValue = 10, totalWidth=12): self.progBar = "" # This holds the progress bar string self.min = minValue self.max = maxValue self.span = maxValue - minValue self.width = totalWidth self.amount = 0 # When amount == max, we are 100% done self.updateAmount(0) # Build progress bar string def updateAmount(self, newAmount = 0): if newAmount < self.min: newAmount = self.min if newAmount > self.max: newAmount = self.max self.amount = newAmount # Figure out the new percent done, round to an integer diffFromMin = float(self.amount - self.min) percentDone = (diffFromMin / float(self.span)) * 100.0 percentDone = round(percentDone) percentDone = int(percentDone) # Figure out how many hash bars the percentage should be allFull = self.width - 2 numHashes = (percentDone / 100.0) * allFull numHashes = int(round(numHashes)) # build a progress bar with hashes and spaces self.progBar = "[" + '#'*numHashes + ' '*(allFull-numHashes) + "]" # figure out where to put the percentage, roughly centered percentPlace = (len(self.progBar) / 2) - len(str(percentDone)) percentString = str(percentDone) + "%" # slice the percentage into the bar self.progBar = self.progBar[0:percentPlace] + percentString + self.progBar[percentPlace+len(percentString):] def __str__(self): return str(self.progBar)
I used this along with curses to display a progress bar while copying a large file over the network. It was better than looking at an apparently "frozen" screen for a long time telling the user that the copy is really happening.
Of course, nothing ties this progress bar to file copy progress. You can use it for anything that takes a while to do and progress can be measured.