gh-35454: fix pycodestyle E502 in coding and crypto folders
    
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### 📚 Description

Fix pycodestyle warnings in `crypto` and `coding` folders.

Done entirely with autopep8.

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URL: #35454
Reported by: Frédéric Chapoton
Reviewer(s): Frédéric Chapoton, Matthias Köppe

Author: Release Manager

src/sage/coding/abstract_code.py

@@ -127,7 +127,7 @@ def _explain_constructor(cl):
         var = "It accepts unspecified arguments as well.\n"
     else:
         var = ""
-    return("{}\n{}\n{}See the documentation of {}.{} for more details."\
+    return("{}\n{}\n{}See the documentation of {}.{} for more details."
             .format(reqs, opts, var, cl.__module__, cl.__name__))
 
 

src/sage/coding/information_set_decoder.py

@@ -583,7 +583,7 @@ def time_search_loop(p):
         def compute_estimate(p):
             iters = 1.* binomial(n, k)/ \
                 sum( binomial(n-tau, k-i)*binomial(tau,i) for i in range(p+1) )
-            estimate = iters*(T + \
+            estimate = iters*(T +
                 sum(P[pi] * (q-1)**pi * binomial(k, pi) for pi in range(p+1) ))
             return estimate
 
@@ -846,7 +846,7 @@ def __init__(self, code, number_errors, algorithm=None, **kwargs):
             self._algorithm = algorithm_names[algorithm](code, number_errors, **kwargs)
         else:
             raise ValueError("Unknown ISD algorithm '{}'."
-                            " The known algorithms are {}."\
+                            " The known algorithms are {}."
                             .format(algorithm, sorted(algorithm_names)))
 
     _known_algorithms = {