<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def is_equal(self, other):
 """ Whether two strings are equal """

        other = StringCell.coerce(other)
        empties = [None,'']
        if self.value in empties and other.value in empties:
            return True
        return self.value == other.value