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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 pair_strings_sum_formatter(a, b):
 """ Formats the sum of a and b. Note ---- Both inputs are numbers already converted to strings. """

  if b[:1] == "-":
    return "{0} - {1}".format(a, b[1:])
  return "{0} + {1}".format(a, b)