gs.core API Reference

The package exports the following API symbols.

String conversion


Convert a string to ASCII, with a reasonable chance of success.

Parameters:stringOrUnicode – The instance to convert.
Returns:The object converted to a string
Return type:str

The to_ascii function, ultimately, calls unicode.encode('ascii', 'ignore'), but it has a couple of advantages.

  1. It takes up less space when writing code.
  2. If passed a string then the string will be decoded as UTF-8, before being re-encoded as ASCII.

The second point may seem to be redundant, but it avoids the dreaded Unicode Decode Error from occurring.


Ensure the filename with the group identifier is ascii:

filename = to_ascii('{0}-members.csv'.format(
gs.core.to_unicode_or_bust(stringOrUnicode, encoding=u'utf-8')[source]

Convert an object to a Unicode instance, with reasonable chance of success.

  • stringOrUnicode – The instance to convert to a unicode.
  • encoding – The encoding for the object. Defaults to utf-8.

The object converted to a Unicode.

Return type:

unicode (or str in Python 3)

Sometimes text-input has… uncertain… origins, and it is hard to know encoding it is. The to_unicode_or_bust has a good stab at converting the input to a Unicode instance.


Convert some input into Unicode:

filename = gs.core.to_unicode_or_bust(someInput)
Taken from an excellent presentation on Unicode in Python by Kumar McMillan.


gs.core.comma_comma_and(l, conj=u'and')[source]

Turn a list of strings into a single string, with commas.

  • l (sequence) – The strings to convert.
  • conj (str) – The conjunctive to use.


  • An empty string if the list l is empty,
  • The one item from l if l is a single item long, or
  • A single string that contains all the items from l separated by commas (,), except for the last two items that are separated by a comma and the conjunctive (conj).

Return type:


This utility turns a list (such as ['this', 'that', 'the other thing']) into a single string (this, that, and the other thing). It is useful when reporting back from forms.

Date functions


Get the current time, in UTC, as a datetime.datetime.

Returns:The current time, as a class:datetime.datetime instance, with the timezone set to UTC.
Return type:datetime.datetime

This function returns the current time, with a timezone, as a standard Python datetime.datetime instance. It saves quite a few imports!



Create a random identifier, using a string as a seed.

Parameters:s (str) – The string to be used as a seed.
Returns:A base-62 encoded string, 22 characters long.
Return type:str

Many things require unique identifiers, such as users, posts, topics, password-reset links, and email-verification links. The to_id function takes a string and converts it to a fixed-length base-62 encoded string that can be used as an ID.


Create a verification identifier for an email address:

email = emailUser.get_delivery_addresses()[0]
verificationId = to_id(email)

Convert an integer to a base-62 encoded string.

Parameters:num (int) – The number to convert.
Returns:A base-62 encoded string.
Return type:str

Creating a mailto URI

gs.core.mailto(toAddress, subject, body)[source]

Create a mailto URI

  • toAddress (str) – The address to send the email to (the To header).
  • subject (str) – The subject of the new message (the Subject header).
  • body (str) – The body of the message

A mailto URI (mailto:).

Return type:


It is possible to create a URI that will create an email message when clicked. Such URIs start with mailto: (RFC 6068). However, care must be taken to quote the parameters correctly. This function creates a mailto URI with the correct quoting.