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KeyErrors while generating a dict

Below is the list of dict using trying to generate dict

data = [
  {'date': datetime.date(2011, 8, 14), 'name': u'ab', 'total': 8},
  {'date': datetime.date(2011, 8, 15), 'name': u'ab', 'total': 8}, 
  {'date': datetime.date(2011, 8, 16), 'name': u'ab', 'total': 8}, 
  {'date': datetime.date(2011, 8, 17), 'name': u'ab', 'total': 8}, 
  {'date': datetime.date(2011, 8, 18), 'name': u'ab', 'total': 8},
  {'date': datetime.date(2011, 8, 19), 'name': u'ab', 'total': 8}, 
  {'date': datetime.date(2011, 8, 20), 'name': u'ab', 'total': 8}, 
  {'date': datetime.date(2011, 8, 21), 'name': u'ab', 'total': 8},
  {'date': datetime.date(2011, 8, 18), 'name': u'aj', 'total': 0},
  {'date': datetime.date(2011, 8, 14), 'name': u'ap', 'total': 8}, 
  {'date': datetime.date(2011, 8, 15), 'name': u'ap', 'total': 8},
  {'date': datetime.date(2011, 8, 16), 'name': u'ap', 'total': 8},
  {'date': datetime.date(2011, 8, 17), 'name': u'ap', 'total': 8},
  {'name': u'ab', 'l_total': 8, 'type': u'UP'}, 
  {'name': u'ab', 'l_total': 8, 'type': u'PL'},
  {'name': u'fk', 'l_total': 29, 'type': u''},
  {'name': u'jw', 'l_total': 1, 'type': u'PD'}, 
  {'name': u'uk', 'l_total': 16, 'type': u'UP'}, 
  {'name': u'sk', 'l_total': 24, 'type': u'PL'},
  {'name': u'ss', 'l_total': 8, 'type': u'PL'},
  {'name': u'sst', 'l_to开发者_开发问答tal': 8, 'type': u'PL'}]



results = collections.defaultdict(dict)

for fetch in data:
        user = fetch['name']
        hrs = fetch['total']
        row = results[user]
        new_y = fetch['type']
        row['new_y'] = fetch['l_total']
        row['user'] = user
        dt_string = str(fetch['date'])
        if dt_string in fetch and row[dt_string] != hr:
          raise Exception, "Contradiction: '%s' on '%s'" % (user, dt_string)
        row[dt_string] = hrs
        row.setdefault('Total', 0)
        row['Total'] += hrs

while generating below output

{u'ap': {'Total': 32, 'user': u'ap', '2011-08-17': 8, 
         '2011-08-16': 8, '2011-08-15': 8, '2011-08-14': 8,
         'up': 8, 'PL':8})

Getting key error,any help really appreciate

Note : Here you find two type of dicts one {'date': datetime.date(2011, 8, 14), 'name': u'ab', 'total': 8}, and another is {'name': u'ab', 'total': 8, 'type': u'UP'},. difference between two is keys. in first dict you find date key and another dict type key


Why shouldn't you get a KeyError? You're asking for the value associated with type from the first row of data and there's no such key.

EDIT:

@agf says this is underhelpful, so let me try again.

The first line of data is

{'date': datetime.date(2011, 8, 14), 'name': u'ab', 'total': 8}

in the loop fetch (btw, variables should be named after nouns, not verbs; function names are verbs) is set to that first row and the following line is executed:

new_y = fetch['type']

Well, that line cannot succeed. There is no entry for type in fetch so, as you have seen, Python throws a KeyError. Change the data so there is such an entry or change the code so it doesn't need it.


Try doing bounds checks for the "date" and "type" key:

for fetch in data:
    if "date" in fetch and "type" in fetch:
        user = fetch['name']
        hrs = fetch['total']
        row = results[user]
        new_y = fetch['type']
        row['type'] = fetch['l_total']
        row['user'] = user
        dt_string = str(fetch['date'])
        if dt_string in fetch and row[dt_string] != hr:
            raise Exception, "Contradiction: '%s' on '%s'" % (user, dt_string)
        row[dt_string] = hrs
        row.setdefault('Total', 0)
        row['Total'] += hrs

A better way to do this is check that each element in the dict has all the keys you'll need.

check = ["name", "total", "user", "type", "1_total", "date"]
for fetch in data:
    if all([i in fetch for i in check]):
        user = fetch["name"]
        . . .
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