code: def STR(self, params):
          
          Ra, Rb, Rc = self.get_three_parameters(self.THREE_PARAMETER_WITH_BRACKETS, params)
  
          if self.is_immediate(Rc):
              if Rb == 'SP' or Rb == 'FP':
                  self.check_arguments(low_registers=(Ra,), imm10_4=(Rc,))
              else:
                  self.check_arguments(low_registers=(Ra, Rb), imm7_4=(Rc,))
  
              def STR_func():
                  for i in range(4):
                      self.memory[self.register[Rb] + self.convert_to_integer(Rc[1:]) + i] = ((self.register[Ra] >> (8 * i)) & 0xFF)
          else:
              self.check_arguments(low_registers=(Ra, Rb, Rc))
  
              def STR_func():
                  for i in range(4):
                      self.memory[self.register[Rb] + self.register[Rc] + i] = ((self.register[Ra] >> (8 * i)) & 0xFF)
  
          return STR_func
docs: STR Ra, [Rb, Rc]
          STR Ra, [Rb, #imm7_4]
          STR Ra, [SP, #imm10_4]
  
          Store Ra into memory as a word
          Ra, Rb, and Rc must be low registers