prompt: You will be provided with a partial code base and an issue statement explaining a problem to resolve.
  <issue>
  Broken multiple interface notation in schema
  ### What I'm trying to achieve
  To use Apollo tooling to generate TS types for the application queries. However, it fails because Saleor's schema uses comma as a separator instead of ampersand. More: https://github.com/apollographql/apollo-tooling/issues/434 
  
  ### Steps to reproduce the problem
  1. Go to mirumee/saleor-dashboard repository and clone it
  2. Copy schema from core to dashboard
  3. `npm run build-types`
  4. Notice that it fails at multiple interface implementation.
  
  </issue>
  <code>
  [start of saleor/graphql/management/commands/get_graphql_schema.py]
  1 from django.core.management.base import BaseCommand
  2 from graphql import print_schema
  3 
  4 from ...api import schema
  5 
  6 
  7 class Command(BaseCommand):
  8     help = "Writes SDL for GraphQL API schema to stdout"
  9 
  10     def handle(self, *args, **options):
  11         self.stdout.write(print_schema(schema))
  12
  [end of saleor/graphql/management/commands/get_graphql_schema.py]
  </code>
  
  I need you to solve this issue by generating a single patch file that I can apply directly to this repository using git apply. Please respond with a single patch file in the following format.
  <patch>
  diff --git a/file.py b/file.py
  --- a/file.py
  +++ b/file.py
  @@ -1,27 +1,35 @@
   def euclidean(a, b):
  -    while b:
  -        a, b = b, a % b
  -    return a
  +    if b == 0:
  +        return a
  +    return euclidean(b, a % b)
   
   
   def bresenham(x0, y0, x1, y1):
       points = []
       dx = abs(x1 - x0)
       dy = abs(y1 - y0)
  -    sx = 1 if x0 < x1 else -1
  -    sy = 1 if y0 < y1 else -1
  -    err = dx - dy
  +    x, y = x0, y0
  +    sx = -1 if x0 > x1 else 1
  +    sy = -1 if y0 > y1 else 1
   
  -    while True:
  -        points.append((x0, y0))
  -        if x0 == x1 and y0 == y1:
  -            break
  -        e2 = 2 * err
  -        if e2 > -dy:
  -            err -= dy
  -            x0 += sx
  -        if e2 < dx:
  -            err += dx
  -            y0 += sy
  +    if dx > dy:
  +        err = dx / 2.0
  +        while x != x1:
  +            points.append((x, y))
  +            err -= dy
  +            if err < 0:
  +                y += sy
  +                err += dx
  +            x += sx
  +    else:
  +        err = dy / 2.0
  +        while y != y1:
  +            points.append((x, y))
  +            err -= dx
  +            if err < 0:
  +                x += sx
  +                err += dy
  +            y += sy
  +
  +    points.append((x, y))
       return points
  
  </patch>
golden_diff: diff --git a/saleor/graphql/management/commands/get_graphql_schema.py b/saleor/graphql/management/commands/get_graphql_schema.py
  --- a/saleor/graphql/management/commands/get_graphql_schema.py
  +++ b/saleor/graphql/management/commands/get_graphql_schema.py
  @@ -8,4 +8,14 @@
       help = "Writes SDL for GraphQL API schema to stdout"
   
       def handle(self, *args, **options):
  -        self.stdout.write(print_schema(schema))
  +        """Support multiple interface notation in schema for Apollo tooling.
  +
  +        In `graphql-core` V2 separator for interaces is `,`.
  +        Apollo tooling to generate TypeScript types using `&` as interfaces separator.
  +        https://github.com/graphql-python/graphql-core/pull/258
  +        """
  +        printed_schema = print_schema(schema)
  +        for line in printed_schema.splitlines():
  +            if "implements" in line:
  +                line = line.replace(",", " &")
  +            self.stdout.write(f"{line}\n")
  
verification_info: {"golden_diff": "diff --git a/saleor/graphql/management/commands/get_graphql_schema.py b/saleor/graphql/management/commands/get_graphql_schema.py\n--- a/saleor/graphql/management/commands/get_graphql_schema.py\n+++ b/saleor/graphql/management/commands/get_graphql_schema.py\n@@ -8,4 +8,14 @@\n     help = \"Writes SDL for GraphQL API schema to stdout\"\n \n     def handle(self, *args, **options):\n-        self.stdout.write(print_schema(schema))\n+        \"\"\"Support multiple interface notation in schema for Apollo tooling.\n+\n+        In `graphql-core` V2 separator for interaces is `,`.\n+        Apollo tooling to generate TypeScript types using `&` as interfaces separator.\n+        https://github.com/graphql-python/graphql-core/pull/258\n+        \"\"\"\n+        printed_schema = print_schema(schema)\n+        for line in printed_schema.splitlines():\n+            if \"implements\" in line:\n+                line = line.replace(\",\", \" &\")\n+            self.stdout.write(f\"{line}\\n\")\n", "issue": "Broken multiple interface notation in schema\n### What I'm trying to achieve\r\nTo use Apollo tooling to generate TS types for the application queries. However, it fails because Saleor's schema uses comma as a separator instead of ampersand. More: https://github.com/apollographql/apollo-tooling/issues/434 \r\n\r\n### Steps to reproduce the problem\r\n1. Go to mirumee/saleor-dashboard repository and clone it\r\n2. Copy schema from core to dashboard\r\n3. `npm run build-types`\r\n4. Notice that it fails at multiple interface implementation.\n", "before_files": [{"content": "from django.core.management.base import BaseCommand\nfrom graphql import print_schema\n\nfrom ...api import schema\n\n\nclass Command(BaseCommand):\n    help = \"Writes SDL for GraphQL API schema to stdout\"\n\n    def handle(self, *args, **options):\n        self.stdout.write(print_schema(schema))\n", "path": "saleor/graphql/management/commands/get_graphql_schema.py"}]}