(self)
return False
Returns ``True`` if 'self' contains no free symbols.

        See Also
        ========
        is_comparable
        sympy.core.expr.is_number
Returns ``True`` if 'self' contains no free symbols.
Returns True if self contains no free symbols .
def is_number(self):
        """Returns ``True`` if 'self' contains no free symbols.

        See Also
        ========
        is_comparable
        sympy.core.expr.is_number

        """
        # should be overriden by subclasses
        return False
def is_number ( self ) : # should be overriden by subclasses return False