text: #! python3
  # coding=utf-8
  #
  
  print('\t=============================================')
  print('\t             CONVERSOR DE PESOS')
  print('\t=============================================')
  print('\tConversor rápido de kgs y lbs.\n\n')
  
  
  lbsperkg = 2.204623
  
  while True:
      esnumero=True
      uni1 = input('> ')
      if uni1 == '':
          break
      for i in uni1:
          if not (i.isdigit() or (i in ',.')):
              esnumero = False
              print('Dato incorrecto. Escribe sólo números.\n')
              break
      if esnumero:
          uni1 = float(uni1)
          print(f'\t{uni1:.2f} kg  = {uni1*lbsperkg:.2f} lbs')
          print(f'\t{uni1:.2f} lbs = {uni1/lbsperkg:.2f} kg')
  