char_map.py

"""
Defines two dictionaries for converting 
between text and integer sequences.
"""

char_map_str = """
' 0
<SPACE> 1
a 2
b 3
c 4
d 5
e 6
f 7
g 8
h 9
i 10
j 11
k 12
l 13
m 14
n 15
o 16
p 17
q 18
r 19
s 20
t 21
u 22
v 23
w 24
x 25
y 26
z 27
"""
# the "blank" character is mapped to 28

char_map = {}
index_map = {}
for line in char_map_str.strip().split('\n'):
    ch, index = line.split()
    char_map[ch] = int(index)
    index_map[int(index)+1] = ch
index_map[2] = ' '