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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def parse_number(d, key, regex, s):
 """Find a number using a given regular expression. If the number is found, sets it under the key in the given dictionary. d - The dictionary that will contain the data. key - The key into the dictionary. regex - A string containing the regular expression. s - The string to search. """

    result = find_number(regex, s)
    if result is not None:
        d[key] = result