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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 get_input(input_func, input_str):
 """ Get input from the user given an input function and an input string """

    val = input_func("Please enter your {0}: ".format(input_str))
    while not val or not len(val.strip()):
        val = input_func("You didn't enter a valid {0}, please try again: ".format(input_str))
    return val