






from __future__ import annotations

from collections import namedtuple
def 						_a    (      a :float	,							a :float	,							a :float )							->			tuple:
 a		  =      namedtuple('''result'''	,							'''name value''' )
 if (voltage, current, power).count(0 ) != 1:
  raise ValueError('''Only one argument must be 0''' )
 elif power < 0:
  raise ValueError(
      '''Power cannot be negative in any electrical/electronics system''' )
 elif voltage == 0:
  return result('''voltage'''	,							power / current )
 elif current == 0:
  return result('''current'''	,							power / voltage )
 elif power == 0:
  return result('''power'''	,							float(round(abs(voltage * current )	,							2 ) ) )
 else:
  raise ValueError('''Exactly one argument must be 0''' )


if __name__ == "__main__":
     import doctest

     doctest.testmod()










def 						_a    (      a :float	,							a :float )							->			float:
 return price * (1 + tax_rate)


if __name__ == "__main__":
     print(f"""{price_plus_tax(100, 0.25) = }""")
     print(f"""{price_plus_tax(125.50, 0.05) = }""")


