diff --git a/requirements.txt b/requirements.txt
index 7b263fe..3d89940 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,6 +6,6 @@ shapely~=1.7.1
 numpy~=1.21.1
 matplotlib~=3.4.2
 pandas~=1.3.0  # because of io.common methods
-sympy==1.5.*  # because of specific expression parsing
+sympy==1.11.*  # because of specific expression parsing
 beautifulsoup4~=4.9.3
 lxml~=4.6.3
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