docs: def get_keys_from_ldap(self, username=None):
          """
          Fetch keys from ldap.
  
          Args:
              username Username associated with keys to fetch (optional)
  
          Returns:
              Array of dictionaries in '{username: [public keys]}' format
  
          """
          result_dict = {}
          filter = ['(sshPublicKey=*)']
          if username is not None:
              filter.append('(uid={})'.format(username))
          attributes = ['uid', 'sshPublicKey']
          results = self.client.search(filter, attributes)
          for result in results:
              result_dict[result.uid.value] = result.sshPublicKey.values
          return result_dict