diff --git a/pysr/export_sympy.py b/pysr/export_sympy.py
index 3c3c5f931..3ea0baf06 100644
--- a/pysr/export_sympy.py
+++ b/pysr/export_sympy.py
@@ -50,6 +50,7 @@
     "max": lambda x, y: sympy.Piecewise((y, x < y), (x, True)),
     "min": lambda x, y: sympy.Piecewise((x, x < y), (y, True)),
     "round": lambda x: sympy.ceiling(x - 0.5),
+    "cond": lambda x, y: sympy.Heaviside(x, H0=0) * y,
 }
 
 
diff --git a/pysr/julia_helpers.py b/pysr/julia_helpers.py
index 7918c5e6d..e2f76090c 100644
--- a/pysr/julia_helpers.py
+++ b/pysr/julia_helpers.py
@@ -94,7 +94,15 @@ def install(julia_project=None, quiet=False, precompile=None):  # pragma: no cov
             ],
         )
         # Try installing again:
-        julia.install(quiet=quiet)
+        try:
+            julia.install(quiet=quiet)
+        except julia.tools.PyCallInstallError:
+            warnings.warn(
+                "PyCall.jl failed to install on second attempt. "
+                + "Please consult the GitHub issue "
+                + "https://github.com/MilesCranmer/PySR/issues/257 "
+                + "for advice on fixing this."
+            )
 
     Main, init_log = init_julia(julia_project, quiet=quiet, return_aux=True)
     io_arg = _get_io_arg(quiet)
diff --git a/pysr/version.py b/pysr/version.py
index 4260786a0..8a8995f2f 100644
--- a/pysr/version.py
+++ b/pysr/version.py
@@ -1,2 +1,2 @@
-__version__ = "0.16.3"
-__symbolic_regression_jl_version__ = "0.22.4"
+__version__ = "0.16.4"
+__symbolic_regression_jl_version__ = "0.22.5"