| email, used as parts of URLs, or included as part of an HTTP POST request. The |
| encoding algorithm is not the same as the :program:`uuencode` program. |
| |
| There are two interfaces provided by this module. The modern interface supports |
| encoding and decoding string objects using all three alphabets. The legacy |
| interface provides for encoding and decoding to and from file-like objects as |
| well as strings, but only using the Base64 standard alphabet. |
| |
n | The modern interface provides: |
n | The modern interface, which was introduced in Python 2.4, provides: |
| |
| |
| .. function:: b64encode(s[, altchars]) |
| |
| Encode a string use Base64. |
| |
| *s* is the string to encode. Optional *altchars* must be a string of at least |
| length 2 (additional characters are ignored) which specifies an alternative |
| .. function:: standard_b64decode(s) |
| |
| Decode string *s* using the standard Base64 alphabet. |
| |
| |
| .. function:: urlsafe_b64encode(s) |
| |
| Encode string *s* using a URL-safe alphabet, which substitutes ``-`` instead of |
n | ``+`` and ``_`` instead of ``/`` in the standard Base64 alphabet. |
n | ``+`` and ``_`` instead of ``/`` in the standard Base64 alphabet. The result |
| can still contain ``=``. |
| |
| |
| .. function:: urlsafe_b64decode(s) |
| |
| Decode string *s* using a URL-safe alphabet, which substitutes ``-`` instead of |
| ``+`` and ``_`` instead of ``/`` in the standard Base64 alphabet. |
| |
| |
| |
| *s* is the string to decode. Optional *casefold* is a flag specifying whether a |
| lowercase alphabet is acceptable as input. For security purposes, the default |
| is ``False``. |
| |
| :rfc:`3548` allows for optional mapping of the digit 0 (zero) to the letter O |
| (oh), and for optional mapping of the digit 1 (one) to either the letter I (eye) |
| or letter L (el). The optional argument *map01* when not ``None``, specifies |
n | which letter the digit 1 should be mapped to (when map01 is not *None*, the |
n | which letter the digit 1 should be mapped to (when *map01* is not ``None``, the |
| digit 0 is always mapped to the letter O). For security purposes the default is |
| ``None``, so that 0 and 1 are not allowed in the input. |
| |
| The decoded string is returned. A :exc:`TypeError` is raised if *s* were |
| incorrectly padded or if there are non-alphabet characters present in the |
| string. |
| |
| |
| |
| .. function:: encodestring(s) |
| |
| Encode the string *s*, which can contain arbitrary binary data, and return a |
| string containing one or more lines of base64-encoded data. |
| :func:`encodestring` returns a string containing one or more lines of |
| base64-encoded data always including an extra trailing newline (``'\n'``). |
| |
t | An example usage of the module:: |
t | An example usage of the module: |
| |
| >>> import base64 |
| >>> encoded = base64.b64encode('data to be encoded') |
| >>> encoded |
| 'ZGF0YSB0byBiZSBlbmNvZGVk' |
| >>> data = base64.b64decode(encoded) |
| >>> data |
| 'data to be encoded' |