increase parsing speed of the header

python/obitools3/parsers/header.pyx

@@ -30,20 +30,27 @@ __re_dict__     = re.compile("""^\{\ *
                                        )
                                     )*\ *\}$""", re.VERBOSE)
 
+__re_val__ = re.compile("""(("[^"]*"|'[^']*') *: *([^,}]+|"[^"]*"|'[^']*') *[,}] *)""")
 
 cdef object __etag__(str x):
+    cdef list elements
+    cdef tuple i
+    
     if __re_int__.match(x):
         v=int(x)
     elif __re_float__.match(x):
         v=float(x)
     elif __re_str__.match(x):
         v=x[1:-1]
+    elif x=='None':
+        v=None
     elif x=='False':
         v=False
     elif x=='True':
         v=True
     elif __re_dict__.match(x):
-        v=eval(x)
+        elements=__re_val__.findall(x)
+        v=dict([(i[1][1:-1],__etag__(i[2])) for i in elements])
     else:
         v=x
     return v