Partially mask a string by replacing a given number of characters with
a fixed character. Masking can start from the beginning or end of the
string. This can be used on data of any type (numbers, longs, and so
on) and when de-identifying structured data we’ll attempt to preserve
the original data’s type. (This allows you to take a long like 123 and
modify it to a string like **3.
.. attribute:: masking_character
Character to use to mask the sensitive values—for example,
* for an alphabetic string such as a name, or 0 for a
numeric string such as ZIP code or credit card number. This
string must have a length of 1. If not supplied, this value
defaults to * for strings, and 0 for digits.
Mask characters in reverse order. For example, if
masking_character is 0, number_to_mask is 14,
and reverse_order is false, then the input string
1234-5678-9012-3456 is masked as 00000000000000-3456.
If masking_character is *, number_to_mask is
3, and reverse_order is true, then the string
12345 is masked as 12***.