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# Question 7: Find and Replace

# For this question you need to define two procedures:

# make_converter(match, replacement)

# Takes as input two strings and returns a converter. It doesn't have

# to make a specific type of thing. Itcan

# return anything you would find useful in apply_converter.

# apply_converter(converter, string)

# Takes as input a converter (produced by make_converter), and

# a string, and returns the result of applying the converter to the

# input string. This replaces all occurrences of the match used to

# build the converter, with the replacement. It keeps doing

# replacements until there are no more opportunities for replacements.

def make_converter(match, replacement):

'''

docstring

'''

code = []

code.append(match)

code.append(replacement)

return code

def apply_converter(converter, string):

'''

docstring

'''

while converter[0] in string:

string = string.replace(converter[0], converter[1], 1)

return string

# For example,

TEST1 = make_converter('aa', 'a')

print(apply_converter(TEST1, 'aaaa'))

# >>> a

TEST2 = make_converter('aba', 'b')

print(apply_converter(TEST2, 'aaaaaabaaaaa'))

# >>> ab

# Note that this process is not guaranteed to terminate for all inputs

# (for example, apply_converter(make_converter('a', 'aa'), 'a') would

# run forever).