def dmp_ground(c, u):
 if (not c):
  return dmp_zero(u)
 for i in range((u + 1)):
  c = [c]
 return c

def dmp_ground ( c , u ) : if ( not c ) : return dmp_zero ( u ) for i in range ( ( u + 1 ) ) : c = [ c ] return c
return a multivariate constant .