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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 indent(s, spaces=4):
 """ Inserts `spaces` after each string of new lines in `s` and before the start of the string. """

    new = re.sub('(\n+)', '\\1%s' % (' ' * spaces), s)
    return (' ' * spaces) + new.strip()