Optimizing BF transpiler

asdf.py

#!/usr/bin/python3

import sys
import itertools

def print_header():
	print('#include <stdio.h>')
	print()
	print()
	print('int main() {')
	print()
	print('char wholemem[30000] = {};')
	print('char * mem = wholemem;')
	print()

def print_footer():
	print()
	print("putchar('\\n');")
	print('}')

source_character_set = {
	'<': lambda x: 'mem -= {};'.format(x),
	'>': lambda x: 'mem += {};'.format(x),
	'+': lambda x: '*mem += {};'.format(x),
	'-': lambda x: '*mem -= {};'.format(x),
	'.': lambda x: 'putchar(*mem);' * x,
	',': lambda x: '*mem = getchar();' * x,
	'[': lambda x: 'while(*mem) {' * x,
	']': lambda x: '}' * x,
}

def main():
	print_header()
	if len(sys.argv) == 1 or sys.argv[1] == '-':
		program = sys.stdin.read()
	else:
		with open(sys.argv[1], 'r') as program_file:
			program = program_file.read()

	for ch, rep in itertools.groupby(filter(lambda c: c in source_character_set, program)):
		print(source_character_set[ch](len(list(rep))))
	print_footer()

if __name__ == '__main__':
	main()