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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 time |
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4 from datetime import timedelta, tzinfo |
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5 from django.utils.encoding import smart_unicode, smart_str, DEFAULT_LOCALE_ENCODING |
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6 |
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7 class FixedOffset(tzinfo): |
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8 "Fixed offset in minutes east from UTC." |
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9 def __init__(self, offset): |
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10 if isinstance(offset, timedelta): |
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11 self.__offset = offset |
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12 offset = self.__offset.seconds // 60 |
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13 else: |
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14 self.__offset = timedelta(minutes=offset) |
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15 |
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16 self.__name = u"%+03d%02d" % (offset / 60, offset % 60) |
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17 |
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18 def __repr__(self): |
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19 return self.__name |
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20 |
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21 def utcoffset(self, dt): |
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22 return self.__offset |
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23 |
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24 def tzname(self, dt): |
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25 return self.__name |
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26 |
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27 def dst(self, dt): |
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28 return timedelta(0) |
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29 |
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30 class LocalTimezone(tzinfo): |
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31 "Proxy timezone information from time module." |
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32 def __init__(self, dt): |
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33 tzinfo.__init__(self) |
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34 self._tzname = self.tzname(dt) |
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35 |
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36 def __repr__(self): |
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37 return smart_str(self._tzname) |
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38 |
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39 def utcoffset(self, dt): |
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40 if self._isdst(dt): |
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41 return timedelta(seconds=-time.altzone) |
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42 else: |
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43 return timedelta(seconds=-time.timezone) |
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44 |
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45 def dst(self, dt): |
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46 if self._isdst(dt): |
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47 return timedelta(seconds=-time.altzone) - timedelta(seconds=-time.timezone) |
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48 else: |
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49 return timedelta(0) |
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50 |
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51 def tzname(self, dt): |
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52 try: |
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53 return smart_unicode(time.tzname[self._isdst(dt)], |
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54 DEFAULT_LOCALE_ENCODING) |
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55 except UnicodeDecodeError: |
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56 return None |
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57 |
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58 def _isdst(self, dt): |
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59 tt = (dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second, dt.weekday(), 0, -1) |
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60 try: |
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61 stamp = time.mktime(tt) |
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62 except (OverflowError, ValueError): |
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63 # 32 bit systems can't handle dates after Jan 2038, and certain |
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64 # systems can't handle dates before ~1901-12-01: |
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65 # |
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66 # >>> time.mktime((1900, 1, 13, 0, 0, 0, 0, 0, 0)) |
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67 # OverflowError: mktime argument out of range |
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68 # >>> time.mktime((1850, 1, 13, 0, 0, 0, 0, 0, 0)) |
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69 # ValueError: year out of range |
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70 # |
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71 # In this case, we fake the date, because we only care about the |
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72 # DST flag. |
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73 tt = (2037,) + tt[1:] |
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74 stamp = time.mktime(tt) |
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75 tt = time.localtime(stamp) |
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76 return tt.tm_isdst > 0 |