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1 "Implementation of tzinfo classes for use with datetime.datetime." |
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2 |
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3 import locale |
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4 import time |
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5 from datetime import timedelta, tzinfo |
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6 from django.utils.encoding import smart_unicode |
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7 |
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8 try: |
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9 DEFAULT_ENCODING = locale.getdefaultlocale()[1] or 'ascii' |
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10 except: |
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11 # Any problems at all determining the locale and we fallback. See #5846. |
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12 DEFAULT_ENCODING = 'ascii' |
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13 |
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14 class FixedOffset(tzinfo): |
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15 "Fixed offset in minutes east from UTC." |
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16 def __init__(self, offset): |
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17 self.__offset = timedelta(minutes=offset) |
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18 self.__name = u"%+03d%02d" % (offset // 60, offset % 60) |
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19 |
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20 def __repr__(self): |
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21 return self.__name |
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22 |
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23 def utcoffset(self, dt): |
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24 return self.__offset |
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25 |
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26 def tzname(self, dt): |
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27 return self.__name |
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28 |
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29 def dst(self, dt): |
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30 return timedelta(0) |
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31 |
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32 class LocalTimezone(tzinfo): |
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33 "Proxy timezone information from time module." |
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34 def __init__(self, dt): |
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35 tzinfo.__init__(self, dt) |
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36 self._tzname = self.tzname(dt) |
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37 |
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38 def __repr__(self): |
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39 return self._tzname |
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40 |
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41 def utcoffset(self, dt): |
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42 if self._isdst(dt): |
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43 return timedelta(seconds=-time.altzone) |
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44 else: |
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45 return timedelta(seconds=-time.timezone) |
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46 |
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47 def dst(self, dt): |
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48 if self._isdst(dt): |
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49 return timedelta(seconds=-time.altzone) - timedelta(seconds=-time.timezone) |
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50 else: |
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51 return timedelta(0) |
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52 |
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53 def tzname(self, dt): |
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54 try: |
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55 return smart_unicode(time.tzname[self._isdst(dt)], DEFAULT_ENCODING) |
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56 except UnicodeDecodeError: |
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57 return None |
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58 |
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59 def _isdst(self, dt): |
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60 tt = (dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second, dt.weekday(), 0, -1) |
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61 try: |
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62 stamp = time.mktime(tt) |
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63 except OverflowError: |
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64 # 32 bit systems can't handle dates after Jan 2038, so we fake it |
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65 # in that case (since we only care about the DST flag here). |
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66 tt = (2037,) + tt[1:] |
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67 stamp = time.mktime(tt) |
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68 tt = time.localtime(stamp) |
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69 return tt.tm_isdst > 0 |