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	Added documentation for the extras module.
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								doc/extras.rst
									
									
									
									
									
								
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			@ -8,4 +8,135 @@
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This module is a generic place used to hold little helper functions and
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classes until a better place in the distribution is found.
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.. todo:: psycopg2.extras
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.. index::
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    pair: Cursor; Dictionary
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.. _dict-cursor:
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Dictionary-like cursor
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----------------------
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The dict cursors allow to access to the retrieved records using an iterface
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similar to the Python dictionaries instead of the tuples. You can use it
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either passing :class:`DictConnection` as :obj:`!connection_factory` argument
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to the :func:`~psycopg2.connect` function or passing :class:`DictCursor` as
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the :class:`!cursor_factory` argument to the :meth:`~connection.cursor` method
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of a regular :class:`connection`. ::
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    >>> conn = psycopg2.connect(database='test')
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    >>> cur = conn.cursor(cursor_factory=psycopg2.extras.DictCursor)
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    >>> cur.execute("SELECT * FROM test")
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    >>> rec['id']
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    1
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    >>> rec['num']
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    100
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    >>> rec['data']
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    "abc'def"
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    # The records still support indexing as the original tuple
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    >>> rec[2]
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    "abc'def"
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.. autoclass:: DictCursor
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.. autoclass:: DictConnection
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.. autoclass:: DictRow
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Real dictionary cursor
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^^^^^^^^^^^^^^^^^^^^^^
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.. autoclass:: RealDictCursor
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.. autoclass:: RealDictConnection
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.. autoclass:: RealDictRow
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.. index::
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    pair: Cursor; Logging
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Logging cursor
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--------------
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.. autoclass:: LoggingConnection
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    :members: initialize,filter
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.. autoclass:: LoggingCursor
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.. autoclass:: MinTimeLoggingConnection
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    :members: initialize,filter
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.. autoclass:: MinTimeLoggingCursor
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.. index::
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    pair: UUID; Data types
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UUID data type
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--------------
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.. versionadded:: 2.0.9
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.. versionchanged:: 2.0.13 added UUID array support.
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::
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    >>> psycopg2.extras.register_uuid()
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    # Python UUID can be used in SQL queries
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    >>> psycopg2.extensions.adapt(uuid.uuid4()).getquoted()
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    "'1ad2b180-c17e-46ad-ad94-e1f0dfc7c34b'::uuid"
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    # PostgreSQL UUID are transformed into Python UUID objects.
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    >>> conn = psycopg2.connect(database='test')
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    >>> cur = conn.cursor()
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    >>> cur.execute("SELECT 'a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11'::uuid")
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    >>> cur.fetchone()[0]
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    UUID('a0eebc99-9c0b-4ef8-bb6d-6bb9bd380a11')
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.. autofunction:: register_uuid
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.. autoclass:: UUID_adapter
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.. index::
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    pair: INET; Data types
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INET data type
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--------------
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::
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    >>> psycopg2.extras.register_inet()
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    >>> conn = psycopg2.connect(database='test')
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    >>> cur = conn.cursor()
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    >>> cur.execute("SELECT '192.168.0.1'::inet")
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    >>> cur.fetchone()[0].addr
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    '192.168.0.1'
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.. autofunction:: register_inet()
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.. autoclass:: Inet
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.. todo:: Adapter non registered: how to register it?
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.. index::
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    single: Time zones; Fractional
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Fractional time zones
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---------------------
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.. versionadded:: 2.0.10
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.. autofunction:: register_tstz_w_secs
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			@ -227,7 +227,9 @@ Many standards Python types are adapted into SQL and returned as Python
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objects when a query is executed.
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If you need to convert other Python types to and from PostgreSQL data types,
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see :ref:`adapting-new-types` and :ref:`type-casting-from-sql-to-python`.
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see :ref:`adapting-new-types` and :ref:`type-casting-from-sql-to-python`.  You
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can also find a few other specialized adapters in the :mod:`psycopg2.extras`
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module.
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In the following examples the method :meth:`~cursor.mogrify` is used to show
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the SQL string that would be sent to the database.
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			@ -97,7 +97,7 @@ class DictCursorBase(_cursor):
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        return res
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class DictConnection(_connection):
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    """A connection that uses DictCursor automatically."""
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    """A connection that uses :class:`DictCursor` automatically."""
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    def cursor(self, name=None):
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        if name is None:
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            return _connection.cursor(self, cursor_factory=DictCursor)
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			@ -180,7 +180,7 @@ class DictRow(list):
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        return self._index.__contains__(x)
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class RealDictConnection(_connection):
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    """A connection that uses RealDictCursor automatically."""
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    """A connection that uses :class:`RealDictCursor` automatically."""
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    def cursor(self, name=None):
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        if name is None:
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            return _connection.cursor(self, cursor_factory=RealDictCursor)
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			@ -193,7 +193,7 @@ class RealDictCursor(DictCursorBase):
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    Note that this cursor is extremely specialized and does not allow
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    the normal access (using integer indices) to fetched data. If you need
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    to access database rows both as a dictionary and a list, then use
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    the generic DictCursor instead of RealDictCursor.
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    the generic :class:`DictCursor` instead of :class:`!RealDictCursor`.
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    """
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    def __init__(self, *args, **kwargs):
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			@ -218,6 +218,7 @@ class RealDictCursor(DictCursorBase):
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            self._query_executed = 0
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class RealDictRow(dict):
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    """A ``dict`` subclass representing a data record."""
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    __slots__ = ('_column_mapping')
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			@ -232,13 +233,16 @@ class RealDictRow(dict):
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class LoggingConnection(_connection):
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    """A connection that logs all queries to a file or logger object."""
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    """A connection that logs all queries to a file or logger__ object.
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    .. __: http://docs.python.org/library/logging.html
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    """
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    def initialize(self, logobj):
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        """Initialize the connection to log to `logobj`.
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        """Initialize the connection to log to ``logobj``.
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        The `logobj` parameter can be an open file object or a Logger instance
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        from the standard logging module.
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        The ``logobj`` parameter can be an open file object or a Logger
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        instance from the standard logging module.
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        """
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        self._logobj = logobj
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        if logging and isinstance(logobj, logging.Logger):
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			@ -294,12 +298,13 @@ class LoggingCursor(_cursor):
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class MinTimeLoggingConnection(LoggingConnection):
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    """A connection that logs queries based on execution time.
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    This is just an example of how to sub-class LoggingConnection to provide
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    some extra filtering for the logged queries. Both the `.inizialize()` and
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    `.filter()` methods are overwritten to make sure that only queries
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    executing for more than `mintime` ms are logged.
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    This is just an example of how to sub-class :class:`LoggingConnection` to
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    provide some extra filtering for the logged queries. Both the
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    :meth:`inizialize` and :meth:`filter` methods are overwritten to make sure
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    that only queries executing for more than ``mintime`` ms are logged.
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    Note that this connection uses the specialized cursor MinTimeLoggingCursor.
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    Note that this connection uses the specialized cursor
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    :class:`MinTimeLoggingCursor`.
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    """
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    def initialize(self, logobj, mintime=0):
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        LoggingConnection.initialize(self, logobj)
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			@ -318,7 +323,7 @@ class MinTimeLoggingConnection(LoggingConnection):
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            return _connection.cursor(self, name, cursor_factory=MinTimeLoggingCursor)
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class MinTimeLoggingCursor(LoggingCursor):
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    """The cursor sub-class companion to MinTimeLoggingConnection."""
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    """The cursor sub-class companion to :class:`MinTimeLoggingConnection`."""
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    def execute(self, query, vars=None, async=0):
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        self.timestamp = time.time()
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    import uuid
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    class UUID_adapter(object):
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        """Adapt Python's uuid.UUID type to PostgreSQL's uuid."""
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        """Adapt Python's uuid.UUID__ type to PostgreSQL's uuid__.
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        .. __: http://docs.python.org/library/uuid.html
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        .. __: http://www.postgresql.org/docs/8.4/static/datatype-uuid.html
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        """
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        def __init__(self, uuid):
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            self._uuid = uuid
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			@ -440,7 +449,7 @@ def _convert_tstz_w_secs(s, cursor):
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        return DATETIME(s[:-3], cursor)
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def register_tstz_w_secs(oids=None, conn_or_curs=None):
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    """Register alternate type caster for TIMESTAMP WITH TIME ZONE.
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    """Register alternate type caster for :sql:`TIMESTAMP WITH TIME ZONE`.
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    The Python datetime module cannot handle time zones with
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    seconds in the UTC offset. There are, however, historical
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			@ -451,16 +460,16 @@ def register_tstz_w_secs(oids=None, conn_or_curs=None):
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    timestamp you likely want to try this type caster. It truncates
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    the seconds from the time zone data and retries casting
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    the timestamp. Note that this will generate timestamps
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    which are INACCURATE by the number of seconds truncated
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    which are **inaccurate** by the number of seconds truncated
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    (unless the seconds were 00).
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    <oids>
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    :param oids:
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            which OIDs to use this type caster for,
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            defaults to TIMESTAMP WITH TIME ZONE
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    <conn_or_curs>
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            defaults to :sql:`TIMESTAMP WITH TIME ZONE`
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    :param conn_or_curs:
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            a cursor or connection if you want to attach
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            this type caster to that only, defaults to
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            None meaning all connections and cursors
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            ``None`` meaning all connections and cursors
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    """
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    if oids is None:
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        oids = (1184,) # hardcoded from PostgreSQL headers
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