diff --git a/pypynum/Symbolics.py b/pypynum/Symbolics.py
index 8071404..ff6a03a 100644
--- a/pypynum/Symbolics.py
+++ b/pypynum/Symbolics.py
@@ -56,7 +56,7 @@ def parse_expr(expr: str) -> list:
         result.append(number)
     if depth != 0:
         raise ValueError("The parentheses in the expression are not paired")
-    return result if len(result) != 1 else result[0]
+    return result
 
 
 # TODO 表达式展开
diff --git a/pypynum/cipher.py b/pypynum/cipher.py
index 6ee06d5..77226b2 100644
--- a/pypynum/cipher.py
+++ b/pypynum/cipher.py
@@ -129,13 +129,13 @@ def substitution(text: str, sub_map: dict, decrypt: bool = False) -> str:
     return result
 
 
-def morse(text: str, decrypt: bool = False) -> str:
+def morse(string: str, decrypt: bool = False) -> str:
     code_dict = MORSE_CODE_REVERSE if decrypt else MORSE_CODE
     result = []
     if decrypt:
-        text = text.split()
+        text = string.split()
     else:
-        text = text.upper()
+        text = string.upper()
     for item in text:
         if item in code_dict:
             result.append(code_dict[item])
diff --git a/pypynum/equations.py b/pypynum/equations.py
index 6cf68e9..7477a8b 100644
--- a/pypynum/equations.py
+++ b/pypynum/equations.py
@@ -1,6 +1,7 @@
-def lin_eq(left: list, right: list) -> list:
-    from .Array import array
-    from .Matrix import mat
+from .Array import array
+from .Matrix import eigen, mat
+def lin_eq(left: list, right: list) :
+
     d = mat(left).det()
     if d != 0:
         return array([mat([left[_][:item] + [right[_]] + left[_][item + 1:] for _ in range(len(left))]).det() / d
@@ -8,9 +9,8 @@ def lin_eq(left: list, right: list) -> list:
     return array([float("inf")] * len(right))
 
 
-def poly_eq(coefficients: list) -> list:
-    from .Array import array
-    from .Matrix import eigen, mat
+def poly_eq(coefficients: list) :
+
     p = [_ / coefficients[0] for _ in coefficients[1:]]
     return array(sorted(eigen(mat([[-p[i] if j == 0 else 1 if i + 1 == j else 0 for j in range(len(p))]
                                    for i in range(len(p))]))[0].diag().t()[0], key=lambda c: (c.real, c.imag)))