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How can I use UUIDs in SQLAlchemy?

... is an example: from sqlalchemy.dialects.postgresql import UUID from flask_sqlalchemy import SQLAlchemy import uuid db = SQLAlchemy() class Foo(db.Model): # id = db.Column(db.Integer, primary_key=True) id = db.Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4, unique=True, n...
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TypeError: 'NoneType' object is not iterable in Python

...r a variable containing None. The operation was performed by invoking the __iter__ method on the None. None has no __iter__ method defined, so Python's virtual machine tells you what it sees: that NoneType has no __iter__ method. This is why Python's duck-typing ideology is considered bad. The...
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How do I make a textbox that only accepts numbers?

... with this two event handlers on a standard TextBox: private void textBox1_KeyPress(object sender, KeyPressEventArgs e) { if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) && (e.KeyChar != '.')) { e.Handled = true; } // only allow one de...
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Calculating frames per second in a game

... like float weightRatio = 0.1; and time = time * (1.0 - weightRatio) + last_frame * weightRatio – korona Nov 11 '08 at 10:04 2 ...
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Types in MySQL: BigInt(20) vs Int(20)

...264 (22003): Out of range value for column 'id' at row 1 mysql> SET sql_mode = ''; Query OK, 0 rows affected, 1 warning (0,00 sec) mysql> INSERT INTO `test` (`id`) VALUES (401421228216); Query OK, 1 row affected, 1 warning (0,06 sec) mysql> SELECT * FROM `test`; +------------+ | id ...
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not None test in Python [duplicate]

...r of the latter two, since val could potentially be of a type that defines __eq__() to return true when passed None. share | improve this answer | follow | ...
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how to return index of a sorted list? [duplicate]

...ray([2,3,1,4,5]) >>> vals array([2, 3, 1, 4, 5]) >>> sort_index = numpy.argsort(vals) >>> sort_index array([2, 0, 1, 3, 4]) If not available, taken from this question, this is the fastest method: >>> vals = [2,3,1,4,5] >>> sorted(range(len(vals)), key=...
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How to exit from Python without traceback?

...Shutdown requested...exiting" except Exception: traceback.print_exc(file=sys.stdout) sys.exit(0) if __name__ == "__main__": main() share | improve this answer | ...
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Inject errors into already validated form?

... Form._errors can be treated like a standard dictionary. It's considered good form to use the ErrorList class, and to append errors to the existing list: from django.forms.utils import ErrorList errors = form._errors.setdefault("m...
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Perform commands over ssh with Python

...o.SSHClient() ssh.connect(server, username=username, password=password) ssh_stdin, ssh_stdout, ssh_stderr = ssh.exec_command(cmd_to_execute) share | improve this answer | fo...