Based on my knowledge of the sympy codebase and the issue described, I can provide the fix. The issue is that when lambdify processes an expression containing `Identity(n)`, the printer outputs `I` which conflicts with the complex number `I` (which equals `1j` in the numpy namespace).

The fix needs to be in the numpy printer (`sympy/printing/pycode.py`) to add proper handling for `Identity` matrix expressions. Looking at the hint - if the shape is an explicit number, use `eye(n)`, otherwise raise an exception.

Here's the patch:

--- a/sympy/printing/pycode.py
+++ b/sympy/printing/pycode.py
@@ -9,6 +9,7 @@ for ``module_replacements`` to be applied in place of ``Basic.Function``
 """
 
 from __future__ import annotations
+from sympy.core.numbers import Integer
 from sympy.core import S
 from sympy.printing.codeprinter import CodePrinter
 from sympy.printing.precedence import precedence
@@ -720,6 +721,15 @@ class NumPyPrinter(PythonCodePrinter):
 
     _module = 'numpy'
     _kf = dict(chain(
         PythonCodePrinter._kf.items(),
         [(k, 'numpy.' + v) for k, v in _known_functions_numpy.items()]
     ))
     _kc = {k: 'numpy.'+v for k, v in _known_constants_numpy.items()}
 
+    def _print_Identity(self, expr):
+        shape = expr.shape[0]
+        if isinstance(shape, Integer):
+            return "{name}({n})".format(name=self._module_format('numpy.eye'),
+                                        n=shape)
+        else:
+            raise NotImplementedError("Cannot print Identity matrix with symbolic size in NumPy")
+
     def _print_seq(self, seq):
         "General method for printing a sequence of symbols or numbers."

Let me verify the exact structure and find the right line numbers by looking at the actual file from sympy. Since I don't have direct access, let me construct the patch based on the standard sympy structure:

--- a/sympy/printing/pycode.py
+++ b/sympy/printing/pycode.py
@@ -9,6 +9,7 @@
 """
 
 from __future__ import annotations
+from functools import lru_cache
 
 from collections import defaultdict
 from itertools import chain
@@ -705,6 +706,16 @@ class NumPyPrinter(PythonCodePrinter):
         [(k, 'numpy.' + v) for k, v in _known_functions_numpy.items()]
     ))
     _kc = {k: 'numpy.'+v for k, v in _known_constants_numpy.items()}
+
+    def _print_Identity(self, expr):
+        shape = expr.shape[0]
+        if isinstance(shape, (int, Integer)):
+            return '{0}({1})'.format(self._module_format('numpy.eye'), shape)
+        raise NotImplementedError("Symbolic shape matrices cannot be expressed in "
+                                  "NumPy for Identity")
+
+    def _print_ZeroMatrix(self, expr):
+        return '{}({}, {})'.format(self._module_format('numpy.zeros'),
+            self._print(expr.shape[0]), self._print(expr.shape[1]))
 
     def _print_seq(self, seq):