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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_multiple(s, f, values=None):
 """Parse multiple comma-separated elements, each of which is parsed using function f."""

    if values is None: values = []
    values.append(f(s))
    if s.pos < len(s) and s.cur == ',':
        s.pos += 1
        return parse_multiple(s, f, values)
    else:
        return values