Merge branch 'polynomials/monomial_coefficients' into lazy_series/pus…

…hout_experiment

src/sage/rings/polynomial/multi_polynomial_ring_base.pyx

@@ -26,6 +26,7 @@ from sage.rings.polynomial import polynomial_ring
 from sage.rings.polynomial.term_order import TermOrder
 from sage.rings.polynomial.polynomial_ring_constructor import (PolynomialRing,
                                           polynomial_default_category)
+from sage.rings.polynomial.polydict import ETuple
 
 
 def is_MPolynomialRing(x):
@@ -617,7 +618,6 @@ cdef class MPolynomialRing_base(CommutativeRing):
         a dict with respect to ``self.variable_names()``.
         """
         # This is probably horribly inefficient
-        from sage.rings.polynomial.polydict import ETuple
         other_vars = list(x.parent().variable_names())
         name_mapping = [(other_vars.index(var) if var in other_vars else -1) for var in self.variable_names()]
         K = self.base_ring()
@@ -1376,9 +1376,17 @@ cdef class MPolynomialRing_base(CommutativeRing):
 
             sage: R.monomial(e)
             x*y^2*z^3
+
+        TESTS:
+
+        Check that ETuples also work::
+
+            sage: from sage.rings.polynomial.polydict import ETuple
+            sage: R.monomial(ETuple(e))
+            x*y^2*z^3
         """
-        if len(exponents) == 1 and isinstance(exponents[0], tuple):
-            return self({exponents[0]: self.base_ring().one()})
+        if len(exponents) == 1 and isinstance((e := exponents[0]), (tuple, ETuple)):
+            return self({e: self.base_ring().one()})
         return self({exponents: self.base_ring().one()})
 
     def monomials_of_degree(self, degree):