query with ExtractHour and calculation like "values(minutes=(ExtractHour('dt_start') * 60))" gives an pytz error: AttributeError: 'int' object has no attribute 'tzinfo'

[Martijnth]

The generated query works fine in MySQL, guess Django still thinks the result is a datetime/timezone object
but it has become an integer because of the calculation.

---

AttributeError Traceback (most recent call last)
<ipython-input-1-b1fc61315659> in <module>()
---> 47 print(a)

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/models/query.py in repr(self)

224
225 def repr(self):

--> 226 data = list(self[:REPR_OUTPUT_SIZE + 1])

227 if len(data) > REPR_OUTPUT_SIZE:
228 data[-1] = "...(remaining elements truncated)..."

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/models/query.py in iter(self)

248 - Responsible for turning the rows into model objects.
249 """

--> 250 self._fetch_all()

251 return iter(self._result_cache)
252

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/models/query.py in _fetch_all(self)

1116 def _fetch_all(self):
1117 if self._result_cache is None:

-> 1118 self._result_cache = list(self._iterable_class(self))

1119 if self._prefetch_related_lookups and not self._prefetch_done:
1120 self._prefetch_related_objects()

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/models/query.py in iter(self)

104 names = extra_names + field_names + annotation_names
105

--> 106 for row in compiler.results_iter():

107 yield dict(zip(names, row))
108

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/models/sql/compiler.py in results_iter(self, results)

840 for row in rows:
841 if converters:

--> 842 row = self.apply_converters(row, converters)

843 yield row
844

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/models/sql/compiler.py in apply_converters(self, row, converters)

825 value = row[pos]
826 for converter in convs:

--> 827 value = converter(value, expression, self.connection, self.query.context)

828 row[pos] = value
829 return tuple(row)

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/db/backends/mysql/operations.py in convert_datetimefield_value(self, value, expression, connection, context)

237 if value is not None:
238 if settings.USE_TZ:

--> 239 value = timezone.make_aware(value, self.connection.timezone)

240 return value
241

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/django/utils/timezone.py in make_aware(value, timezone, is_dst)

283 if hasattr(timezone, 'localize'):
284 # This method is available for pytz time zones.

--> 285 return timezone.localize(value, is_dst=is_dst)

286 else:
287 # Check that we won't overwrite the timezone of an aware datetime.

/Users/martijntenhoor/projects/bluebi/rms-drf-api/virtual/lib/python3.5/site-packages/pytz/init.py in localize(self, dt, is_dst)

225 Convert naive time to local time
226 print(dt)

--> 227 if dt.tzinfo is not None:

228 raise ValueError('Not naive datetime (tzinfo is already set)')
229 return dt.replace(tzinfo=self)

AttributeError: 'int' object has no attribute 'tzinfo'