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Given the following text description, write Python code to implement the functionality described.
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Description:
 Return list of all prefixes from shortest to longest of the input string
    
This is how the function will work:
 all_prefixes('abc')
    ['a', 'ab', 'abc']
    
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Python Code:
from typing import List
def all_prefixes(string: str) -> List[str]:
    
    result = []
    for i in range(len(string)):
        result.append(string[:i+1])
    return result
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