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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 _f90repr(self, value):
 """Convert primitive Python types to equivalent Fortran strings."""

        if isinstance(value, bool):
            return self._f90bool(value)
        elif isinstance(value, numbers.Integral):
            return self._f90int(value)
        elif isinstance(value, numbers.Real):
            return self._f90float(value)
        elif isinstance(value, numbers.Complex):
            return self._f90complex(value)
        elif isinstance(value, basestring):
            return self._f90str(value)
        elif value is None:
            return ''
        else:
            raise ValueError('Type {0} of {1} cannot be converted to a Fortran'
                             ' type.'.format(type(value), value))