Python: encontrando valor dentro de uma lista de dicionários

locate_value_in_list_of_dictonaries.py

def in_dictlist(key, value, my_dictlist):
    '''
    Verify if an value is contained in a dictionary list.

    :param key: KEY where the VALUE will be searchead
    :param value: VALUE to be found
    :param my_dictlist: Dictionary where the search will be make it
    :return: TRUE if "value" (param) exists in "my_dictlist" (param)
    '''
    for this in my_dictlist:
        if this[key] == value:
            return True
    return False

  
  list_dict = [
    {"source": "item1"},
    {"source": "item2"},
    {"source": "item3"},
  ]
  
  if in_dictlist("source", "item3", list_dict):
    print('Found')
  else:
    print('NOT found')