Collecting a range of keys from a dictionary - for-loop

Question

I am stumped. I have a Timesheet class that holds work days in a dictionary called self.timesheet with dates as the keys and hours, rate as values. I am trying to write a function that can show all the entries in a user defined range of dates.
for now lets assume the key dates are simple integers 20 - 25. i tried this and it didn't do anything at all. no errors, just nothing.
def show_days(self):
date_from = input("From date: ")
date_to = input("To date: ")
t = self.timesheet
for dates in t[date]:
range(date_from, date to)
print(dates)
I can see this doesn't look right , I feel I need *for dates in range(date_from, date_to)* but I can't figure how to get it to loop over the dictionary keys like that.

Answer 1

You need to loop over the range, then check if that key is in the dictionary:
for day in range(date_from, date_to + 1):
if day in t:
print day, t[day]
Note that the values produced by range() do not include the end point, so I used date_to + 1 to ensure it is included anyway.
If your keys are not integers but, say, datetime.date objects, you'll have to construct some kind of loop with datetime.timedelta() to iterate over all dates between two values:
date = date_from = datetime.date(2012, 1, 15)
date_to = datetime.date(2012, 3, 12)
while date <= date_to:
if date in t:
print date, t[date]
date += datetime.timedelta(days=1)