python-3.7

问题 How can I upgrade values from a base dataclass to one that inherits from it? Example (Python 3.7.2) from dataclasses import dataclass @dataclass class Person: name: str smell: str = "good" @dataclass class Friend(Person): # ... more fields def say_hi(self): print(f'Hi {self.name}') friend = Friend(name='Alex') f1.say_hi() prints "Hi Alex" random_stranger = Person(name = 'Bob', smell='OK') return for random_stranger "Person(name='Bob', smell='OK')" How do I turn the random_stranger into a

问题 I have read and read again the Python documentation about multiprocessing module and Queues management but I cannot find anything related to this issue that turns me crazy and is blocking my project: I wrote a 'JsonLike' class which allows me to create an object such as : a = JsonLike() a.john.doe.is.here = True ...without considering intermediate initialization (very useful) The following code just creates such an object, set and insert it in a array and tries to send that to a process (this

问题 My main goal is to rewrite this javascript into python password = "AAAABBBBCCCC"; passwordMd5 = CryptoJS.MD5(password); //e1b6b2b3211076a71632bbf2ad0edc05 passwordKey = CryptoJS.SHA256(CryptoJS.SHA256(passwordMd5 + data.v1) + data.v2); //4a5148da63f40e1bcd3e3225f9b79412b7aee745f4b7f831b9d0893d0d6d666f encryptedPassword = CryptoJS.AES.encrypt(passwordMd5, passwordKey, {mode: CryptoJS.mode.ECB,padding: CryptoJS.pad.NoPadding}); //U2FsdGVkX198V2FiYyEGAKISlXBcmad7V0scbooxQ8QMSmp84vtyAfHytynX2mrw

问题 I'm writing an inventory database program. I'm a novice so I'm sure I have something wrong. def select_item(): #Create a Database or Connect to one conn = sqlite3.connect('inventory.db') #Create Cursor c = conn.cursor() a = id_select.get() c.execute("SELECT * FROM inventory WHERE oid = " + a) records = c.fetchall() for record in records: Item_editor.insert(0, record[0]) Quantity_editor.insert(0, record[1]) Asset_tag_editor.insert(0, record[2]) Notes_editor.insert(0, record[3]) #Entry Fields

问题 I am trying to import sklearn in my jupyter notebook on a macOS Mojave 10.14.3. macOS comes standard with python 2.7. I have installed python3 in addition python 2.7. I am launching jupyter from a virtual env with python3. When I launch jupyter and open a notebook it shows it is running python 3.7.x. When I list "!pip show scipy" from inside the notebook it says scipy 1.2.1 is installed. Still, with all the above, when I say "import scikit" or "import sklearn" I get a ModuleNotFoundError: No

问题 Django Tutorial part 4 I am getting a NoReverseMatch at /polls/1/ NoReverseMatch at /polls/1/ Reverse for 'polls.index' not found. 'polls.index' is not a valid view In template /var/www/html/django_app/polls/templates/polls/detail.html, error at line 5 Reverse for 'polls.index' not found. 'polls.index' is not a valid view function or pattern name... I have looked up and researched this question on here for a while and am hitting a wall. There are many references to the problem but none that

问题 I'm trying to get the last record in one table connected to another one using many-to-one relationship in django models. Here's my django models: class DataCollecttion(models.Model): default_name = models.CharField(max_length=100) class NameHistory(models.Model): old_name = models.CharField(max_length=100) collection_data = models.ForeignKey(DataCollection, on_delete=models.CASCADE, null=True) Here I created a sample data for DataCollection table: And here's the sample data for NameHistory

问题 It seems that a successful test of the existence of a windows named pipe by using os.path.exists() prevents the pipe from working. Why would this be? Here is successfully working windows named-pipe code: import time import multiprocessing as mp import win32pipe, win32file PIPENAME = r'\\.\pipe\Foo' def producer(pipe_name: str): print('producer') # if not os.path.exists(pipe_name): # print(f'No pipe {pipe_name}') # return pipe = win32file.CreateFile(pipe_name, win32file.GENERIC_READ |

问题 It seems that a successful test of the existence of a windows named pipe by using os.path.exists() prevents the pipe from working. Why would this be? Here is successfully working windows named-pipe code: import time import multiprocessing as mp import win32pipe, win32file PIPENAME = r'\\.\pipe\Foo' def producer(pipe_name: str): print('producer') # if not os.path.exists(pipe_name): # print(f'No pipe {pipe_name}') # return pipe = win32file.CreateFile(pipe_name, win32file.GENERIC_READ |

问题 I am running a simple example: import gmaps import gmaps.datasets gmaps.configure(api_key="...") earthquake_df = gmaps.datasets.load_dataset_as_df( 'earthquakes' ) locations = earthquake_df[[ 'latitude' , 'longitude' ]] weights = earthquake_df[ 'magnitude' ] fig = gmaps.figure() fig.add_layer(gmaps.heatmap_layer(locations, weights=weights)) fig but instead of seeing a heatmap, the output shows this: Figure(layout=FigureLayout(height='420px')) I am using Spyder (Python 3.7) 回答1: ( Spyder