How to avoid too many Try/except?

Question

I have the code below that plays values inside keys in a dictionary. However, I need several try / except so that the code works perfectly, since, in the absence of one of the fields, the code will return a Keyerror Exception and the code will break.

Is there a more optimized and/or simpler way to solve the problem?

Code:

issue_fmt = {}
issue_fmt['assignee'] = {}
issue_fmt['assignee']['display_name'] = ''
issue_fmt['reporter'] = {}
issue_fmt['reporter']['display_name'] = ''
issue_fmt['key'] = ''
issue_fmt['project'] = {}
issue_fmt['project']['name'] = ''

def format_doc(issue):

    try:
        issue_fmt['assignee']['display_name'] = issue['assignee']['display_name']
    except:
        issue_fmt['assignee']['display_name'] = ''
    try:
        issue_fmt['reporter']['display_name'] = issue['reporter']['display_name']
    except:
        issue_fmt['reporter']['display_name'] = ''
    try:
        issue_fmt['key'] = issue['key']
    except:
        issue_fmt['key'] = ''
    try:
        issue_fmt['description'] = issue['description']
    except:
        issue_fmt['description'] = ''
    try:
        issue_fmt['project']['name'] = issue['project']['name']
    except:
        issue_fmt['project']['name'] = '' 

    return dict(issue_fmt)

Answer 1

The dictionary has a method get which you can take as the second parameter a value that will be returned when the fetched key does not exist. So instead:

try:
    issue_fmt['assignee']['display_name'] = issue['assignee']['display_name']
except:
    issue_fmt['assignee']['display_name'] = ''

Just you do

issue_fmt['assignee']['display_name'] = issue['assignee'].get('display_name', '')

So it would be:

def format_doc(issue):
    issue_fmt['assignee']['display_name'] = issue['assignee'].get('display_name', '')
    issue_fmt['reporter']['display_name'] = issue['reporter'].get('display_name')
    issue_fmt['key'] = issue.get('key', '')
    issue_fmt['description'] = issue.get('description', '')
    issue_fmt['project']['name'] = issue['project'].get('name', '')

    return dict(issue_fmt)

But other points should be considered:

1. Why issue_fmt is defined outside the function and not within it?
2. If issue_fmt is already a dictionary, why return dict(issue_fmt)?