Refact/refactorize code

src/symbols/block.py

@@ -43,7 +43,7 @@ def __eq__(self, other):
     def __hash__(self):
         return id(self)
 
-    def pop(self, pos: int) -> Symbol:
+    def pop(self, pos: int = -1) -> Symbol:
         return self.children.pop(pos)
 
     def append(self, *args):

src/symbols/symbol_.py

@@ -9,7 +9,6 @@
 #                    the GNU General License
 # ----------------------------------------------------------------------
 
-import re
 from collections import Counter
 
 from typing import Optional
@@ -78,25 +77,6 @@ def t(self):
 
         return self._t
 
-    def copy_attr(self, other):
-        """ Copies all other attributes (not methods)
-        from the other object to this instance.
-        """
-        if not isinstance(other, Symbol):
-            return  # Nothing done if not a Symbol object
-
-        tmp = re.compile('__.*__')
-        for attr in (x for x in dir(other) if not tmp.match(x)):
-            if (
-                hasattr(self.__class__, attr) and
-                str(type(getattr(self.__class__, attr)) in ('property', 'function', 'instancemethod'))
-            ):
-                continue
-
-            val = getattr(other, attr)
-            if isinstance(val, str) or str(val)[0] != '<':  # Not a value
-                setattr(self, attr, val)
-
     @property
     def is_needed(self) -> bool:
         return len(self.required_by) > 0