import string

print(string.ascii_lowercase)
print(string.ascii_uppercase)
print(string.ascii_letters)
print(string.digits)
print(string.hexdigits)
print(string.octdigits)
print(string.punctuation)
print(string.printable)

abcdefghijklmnopqrstuvwxyz
ABCDEFGHIJKLMNOPQRSTUVWXYZ
abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ
0123456789
0123456789abcdefABCDEF
01234567
!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~
0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ!"#$%&'()*+,-
 ./:;<=>?@[\]^_`{|}~

import string

values = {'var': 'foo'}

t = string.Template("""
Variable : $var
Escape  : $$
Variable in text: ${var}iable
""")

print('TEMPLATE:', t.substitute(values))

s = """
Variable : %(var)s
Escape  : %%
Variable in text: %(var)siable
"""

print('INTERPOLATION:', s % values)

s = """
Variable : {var}
Escape  : {{}}
Variable in text: {var}iable
"""

print('FORMAT:', s.format(**values))

$ python string_template.py

TEMPLATE:
Variable : foo
Escape  : $
Variable in text: fooiable

INTERPOLATION:
Variable : foo
Escape  : %
Variable in text: fooiable

FORMAT:
Variable : foo
Escape  : {}

import string
class MyTemplate(string.Template):
 delimiter = '%'
 idpattern = '[a-z]+_[a-z]+'


template_text = '''
 Delimiter : %%
 Replaced : %with_underscore
 Igonred : %notunderscored
'''


d = {
 'with_underscore': 'replaced',
 'notunderscored': 'not replaced',
}

t = MyTemplate(template_text)
print('Modified ID pattern:')
print(t.safe_substitute(d))

$ python string_template_advanced.py
Modified ID pattern:

 Delimiter : %
 Replaced : replaced
 Igonred : %notunderscored